All calculators
Every free calculator in one place, grouped by category. Each one runs entirely in your browser and shows the formula behind the result.
Engineering
193 calculatorsAeroacoustic Noise Calculator
Estimate aerodynamically generated noise from turbulent flow.
Open instrumentAeroelastic Flutter Calculator
Find the aeroelastic flutter boundary for a nonlinear structure.
Open instrumentAirfoil Lift & Drag Calculator
Compute airfoil lift and drag coefficients for a given angle of attack and flow.
Open instrumentAnchor Bolt Calculator
Cast-in anchor bolt capacity in tension to ACI 318-19 Chapter 17, with steel, breakout and pullout modes and the edge-distance factors.
Open instrumentAngle and Channel Properties
Centroidal properties for angle and channel sections.
Open instrumentANOVA Calculator
One-way ANOVA across three groups with F ratio, p-value and variance explained.
Open instrumentArc Flash Calculator
Arc flash incident energy, arc flash boundary and PPE category to IEEE 1584, with the arcing current.
Open instrumentAS 3600 Concrete Shear
AS 3600 cl.
Open instrumentASCE 7 Wind Load Calculator
Velocity pressure and net design wind pressure from basic wind speed, exposure, gust and pressure coefficients, with force on an area.
Open instrumentASME Pipe Thickness Calculator
Required pipe wall thickness to ASME B31.
Open instrumentBandwidth & Data Throughput Calculator
Calculate data throughput and bandwidth for a link or channel.
Open instrumentBase Plate Calculator
Steel base plate sizing to AISC §J8 and Design Guide 1, with the confinement credit, cantilever projections and required plate thickness.
Open instrumentBase Plate Design
AISC DG1 cantilever model for a concentrically loaded base plate.
Open instrumentBattery Runtime Calculator
Battery runtime with Peukert correction, depth of discharge, inverter and temperature derating, plus the recharge time.
Open instrumentBeam Deflection & Stress Calculator
Euler-Bernoulli finite-element solver: deflection, shear and moment for point and distributed loads.
Open instrumentBeam Shear Calculator
Concrete and stirrup shear capacity to ACI 318, with the d/2 spacing limit and utilisation.
Open instrumentBearing Life Calculator
L10 rating life from dynamic capacity, equivalent load and speed, converted to hours and adjusted for 90–99% reliability.
Open instrumentBolt Torque Calculator
Bolt preload and tightening torque from the RCSC minimum pretension, with the tensile stress area, shank stress and torque-coefficient scatter.
Open instrumentBox Fill Calculator
Electrical box fill to NEC §314.
Open instrumentBrayton Cycle Calculator
Brayton cycle efficiency and work from the pressure ratio and firing temperature, with compressor and turbine efficiencies.
Open instrumentBridge Load Rating
AASHTO MBE load rating: RF = (φRn − γDC·DC − γDW·DW)/(γLL(LL+IM)).
Open instrumentBuilding Energy Estimate
Annual heating and cooling energy and cost from envelope UA, degree-days, plant efficiency and COP.
Open instrumentCable Ampacity Calculator
Conductor ampacity from NEC Table 310.
Open instrumentCable Pulling Tension
Capstan equation through bends; sidewall pressure at the radius.
Open instrumentChiller Plant Sizing
Tons, COP and kW/ton conversions.
Open instrumentCoil Geometry Calculator
Face area, circuit velocity, Darcy-Weisbach water pressure drop and air-side drop from the tube and fin geometry.
Open instrumentCold-Formed Steel Check
AISI S100 §E2 with φc = 0.
Open instrumentColumn Buckling Calculator
Find the Euler-Bernoulli critical buckling load for a column.
Open instrumentColumn Interaction Diagram
P–M interaction curve for a reinforced concrete column, with Bresler biaxial screening.
Open instrumentCompressible Flow & Shock Wave Calculator
Solve isentropic compressible-flow and normal-shock relations by Mach number.
Open instrumentComputational Fluid Dynamics Calculator
Explore computational fluid dynamics (CFD) flow fields and solver outputs.
Open instrumentConcrete Anchor Design
Cast-in anchor design to ACI 318-19: steel tension, concrete breakout, pullout, steel shear and pryout, with the governing state named.
Open instrumentConcrete Beam Design Calculator
Required steel area and φMn for a rectangular reinforced concrete beam to ACI 318, with minimum steel and tension-control checks.
Open instrumentConcrete Calculator
Concrete volume for slabs, footings, walls and columns, plus the ACI 211.
Open instrumentConcrete Column Calculator
Axial capacity of a tied reinforced concrete column to ACI 318, with steel limits and a slenderness check.
Open instrumentConcrete Torsion Check
ACI 318 §22.
Open instrumentConduit Fill Calculator
Conduit fill to NEC Chapter 9 Tables 1, 4 and 5, with the maximum conductor count and the smallest trade size that passes.
Open instrumentConfidence Interval Calculator
Confidence interval for a mean from the sample mean, standard deviation and size.
Open instrumentConsolidation Settlement Calculator
One-dimensional consolidation settlement, strain and time to 50% and 90% from Cc, e0, cv and the drainage path.
Open instrumentControl Valve Calculator
Liquid and gas control valve sizing to IEC 60534: required Cv and Kv, choked-flow limits, cavitation index and installed valve authority.
Open instrumentConvection Calculator
Convection coefficient from the standard Nusselt correlations for a flat plate, a pipe bore and a vertical surface.
Open instrumentCooling Coil Selection Calculator
Apparatus dew point, bypass factor, rows, condensate and chilled-water flow for a cooling coil, with the part-load capacity curve.
Open instrumentCooling Load Calculator
Sensible and latent cooling load from room and supply air conditions, with psychrometric state and SHR.
Open instrumentCooling Tower and Chiller Plant
Cooling tower range, approach, evaporation, blowdown and makeup, with chiller power, COP and running cost.
Open instrumentCrane Load Calculator
ASCE 7 §4.
Open instrumentCSA S16 Steel Check
CSA S16 cl.
Open instrumentDaylighting Calculator
Split-flux daylight factor, BRE guidance.
Open instrumentDecibel Calculator
Convert between ratios and decibels for power and amplitude, add incoherent sources, and apply inverse-square distance loss.
Open instrumentDiscrete Fourier Transform (DFT) Calculator
Compute the discrete Fourier transform spectrum of a signal.
Open instrumentDistillation Calculator
Binary distillation design: minimum stages, minimum reflux, the Gilliland stage count and the McCabe-Thiele construction.
Open instrumentDuct Fitting Losses
Δp = K·0.
Open instrumentDuct Network Calculator
Total pressure loss across three duct segments, split into friction and fittings, with fan power.
Open instrumentDuct Sizing Calculator
Circular duct diameter from airflow and target velocity, with Darcy friction factor and pressure gradient.
Open instrumentEccentric Bolt Group
Vector-sum the direct and torsional shear on every bolt in an eccentric group, and find the critical bolt.
Open instrumentEconomiser Saving Calculator
Net energy and cost saving from an air-side economiser, after the fan penalty.
Open instrumentElastoplastic Damage Calculator
Model nonlinear elastoplastic material damage under load.
Open instrumentElliptic Curve Cryptography Calculator
Perform elliptic-curve point and scalar operations used in modern cryptography.
Open instrumentEurocode 3 Steel Check
Cross-section, shear, flexural buckling and bending to EN 1993-1-1, with the buckling curve and reduction factor exposed.
Open instrumentFan Curve Calculator
Operating point from the fan and system curve, with affinity-law scaling and part-speed power.
Open instrumentFatigue Life Calculator
Fatigue life from the corrected endurance limit, the S-N curve, Goodman mean-stress correction and Miner damage accumulation.
Open instrumentFillet Weld Calculator
Fillet weld design strength from the throat area, with the base-metal check, AISC minimum and maximum sizes and the length required for a load.
Open instrumentFin Efficiency Calculator
Fin efficiency from mL for a straight rectangular fin, with surface efficiency, the useful length and the heat transferred by the array.
Open instrumentFinite Element Method (FEM) Calculator
Run finite-element method mesh calculations for structural problems.
Open instrumentFinite Element Stress Calculator
Compute finite-element stress tensors for a loaded part.
Open instrumentFlange Rating (ASME B16.5)
ASME B16.
Open instrumentFlash Steam Calculator
Flash steam fraction and recovery value from a condensate pressure drop, with the flash line size and the annual energy saving.
Open instrumentFlashing Control Valve Calculator
Control valve Cv in flashing and cavitating service, with the choked pressure drop and the cavitation index.
Open instrumentFloor Vibration Check
AISC Design Guide 11 frequency criterion.
Open instrumentFooting Design Calculator
Isolated footing sizing to ACI 318 with one-way and punching shear, flexural steel and the bearing check.
Open instrumentFractional Factorial Calculator
Build a fractional factorial, read its defining relation and alias groups, block it on a term you can afford to lose, and estimate the effects.
Open instrumentFracture Mechanics Calculator
Stress intensity, toughness ratio, load ratio and the BS 7910 Option 1 failure assessment diagram, with critical crack size.
Open instrumentFrame Analysis Calculator
Stiffness-method portal frame analysis with a geometric stiffness matrix: sway, member forces, P-Δ amplification and the elastic buckling factor.
Open instrumentFrame Load Combinations Calculator
Builds wind and seismic lateral loads to ASCE 7, applies the six strength combinations and re-solves the frame for each to find the governing case.
Open instrumentFrame Model Calculator
Type any nodes, members and point loads, solve the second-order frame and pull the natural frequencies out of the same stiffness matrix.
Open instrumentGas Radiation Calculator
Radiation from a participating gas by the weighted-sum-of-gray-gases model, with the emissivity, absorptivity and wall heat flux.
Open instrumentGear Ratio Calculator
Gear ratio from tooth counts, plus output speed, output torque and efficiency for a single or two-stage train.
Open instrumentGrounding Conductor Calculator
Grounding electrode conductor from Table 250.
Open instrumentGrounding Grid Calculator
IEEE 80 step and touch voltage limits, grid resistance and ground potential rise, plus cable pulling tension.
Open instrumentHarmonic Analysis
THD and the K-factor transformer rating.
Open instrumentHeat Conduction Calculator
Steady-state conduction through a single or layered wall: thermal resistance, heat flux and surface temperatures.
Open instrumentHeat Exchanger Calculator
Counterflow exchanger duty, LMTD, NTU and effectiveness, with the area implied by each method.
Open instrumentHeat Loss Calculator
Fabric and ventilation heat loss from U-value, area, temperature difference and air change rate.
Open instrumentHeat Transfer Calculator
Solve radiative and conjugate heat-transfer problems.
Open instrumentHSS Section Properties
Section properties from geometry; closed-section torsion.
Open instrumentHydraulic Cylinder Calculator
Push and pull force from bore, rod and pressure, plus stroke speed from pump flow and the hydraulic power behind both.
Open instrumentHypersonic Reentry Heating Calculator
Estimate hypersonic reentry heating and thermal-protection requirements.
Open instrumentIdeal Gas Law Calculator
Solve the ideal gas law for pressure, volume, moles or temperature, with density and specific-volume readouts.
Open instrumentInsulation Thickness Calculator
Economic pipe insulation thickness from the heat-loss cost curve, with the critical radius and the annual energy saving.
Open instrumentLateral Pile Analysis
Hetényi beam on an elastic foundation; long-pile closed form.
Open instrumentLattice Boltzmann Flow Calculator
Simulate mesoscopic fluid flow with the lattice Boltzmann method.
Open instrumentLayered Slope Stability Calculator
Layered slope stability by Janbu’s simplified method on a non-circular surface, with the f₀ correction and the critical layer.
Open instrumentLighting Calculator
Lumen-method lighting design: room cavity ratio, coefficient of utilisation, fixture count, delivered lux and power density.
Open instrumentLiquefaction Assessment
Seed–Idriss simplified CSR with the CRR curve for (N1)60cs.
Open instrumentMasonry Wall Calculator
Reinforced masonry wall check to TMS 402 with slenderness, allowable axial stress, out-of-plane bending and the interaction ratio.
Open instrumentMat Foundation (Rigid Method)
Rigid-mat bearing pressure from P/A ± M/S and the ACI 318 punching-shear check.
Open instrumentMotor FLA Calculator
Motor full-load current from NEC Table 430.
Open instrumentMotor Sizing Calculator
Peak torque from load torque and reflected inertia, with shaft power and the effect of acceleration time.
Open instrumentMotor Starting Voltage Dip
Dip from the starting kVA against the fault level.
Open instrumentNavier-Stokes (RANS) Calculator
Solve Reynolds-averaged Navier-Stokes turbulence closures.
Open instrumentNetwork Latency Calculator
Estimate distributed-consensus and network latency across a cluster.
Open instrumentNPSH Calculator
NPSHa from atmospheric pressure, vapour pressure, static head and suction friction, with the margin over the pump NPSHr requirement.
Open instrumentOEE Calculator
OEE from planned time, downtime, ideal cycle and counts, with the loss decomposition behind each factor.
Open instrumentOhm's Law Calculator
Solve voltage, current, resistance and power from any two knowns.
Open instrumentOpen Channel Flow Calculator
Open-channel discharge by Manning for rectangular, trapezoidal, triangular and part-full circular sections, with Froude and critical depth.
Open instrumentOptimal Design Calculator
Coordinate exchange over a candidate set to maximise |X′X|, for a box region or a mixture simplex, with D-efficiency and prediction variance.
Open instrumentOptional Method Service Load Calculator
Dwelling service load by the NEC optional method, with the 100%/40% general-load factor, the HVAC clauses and a standard-method comparison.
Open instrumentOrbital Mechanics Calculator
Compute Keplerian orbital elements and spacecraft state vectors.
Open instrumentOrifice Flow Calculator
Orifice flow for liquids and gases, with the discharge coefficient, the critical pressure ratio and the choked-flow limit.
Open instrumentPhotonic Band Structure Calculator
Compute photonic-crystal band structures and photonic band gaps.
Open instrumentPID Tuning Calculator
PID tuning from a first-order-plus-dead-time model, comparing Ziegler-Nichols, Cohen-Coon and IMC gains and times side by side.
Open instrumentPile Cap Design
ACI 318 §22.
Open instrumentPile Capacity Calculator
Axial pile capacity by the Meyerhof method for sand and clay, with tip and shaft contributions, the L/D cap and the allowable load.
Open instrumentPile Group Calculator
Pile group capacity with the Converse-Labarre efficiency and the undrained block-failure check, showing which governs at a given spacing.
Open instrumentPile Settlement Calculator
Pile group settlement by the equivalent raft method, with the soil compression beneath the raft and the elastic shortening of the piles.
Open instrumentPipe Friction Loss Calculator
Friction head loss and pressure drop for a pipe run using Darcy-Weisbach with the Colebrook friction factor.
Open instrumentPipe Stress Analysis
Free thermal growth, restrained axial stress, guided-cantilever bending and the ASME B31.
Open instrumentPipe Support Loads
Pipe, insulation and contents over the span.
Open instrumentPlasma (MHD) Field Calculator
Solve plasma magnetohydrodynamic (MHD) field equations.
Open instrumentPortal Frame Analysis
Linear static 3D frame analysis with a 12-degree-of-freedom beam element.
Open instrumentPower Factor Correction Calculator
Size a correction capacitor bank from present to target power factor, with line-current relief and per-phase capacitance.
Open instrumentPower Flow Calculator
AC power flow for a three-bus network by Newton-Raphson, with bus voltages, line flows, losses and convergence.
Open instrumentPressure Vessel Shell
Cylindrical shell thickness for internal pressure to ASME VIII Div.
Open instrumentPrestressed Concrete Stresses
Elastic fibre stresses with effective prestress.
Open instrumentProcess Capability Calculator
Cp, Cpk, sigma-to-limit and estimated defect rate from the process mean, standard deviation and specification limits.
Open instrumentProjectile Motion Calculator
Range, apex height, time of flight and impact speed for a projectile launched over level ground, with or without drag.
Open instrumentProtective Device Coordination
Compare two protective devices on their IEC 60255 curves: trip times at the fault, the margin between them, and the TMS the upstream device needs.
Open instrumentPsychrometric Calculator
Psychrometric state from dry bulb and relative humidity, wet bulb or humidity ratio: dew point, enthalpy, specific volume and density to ASHRAE.
Open instrumentPump and System Curve
The operating point where the pump curve meets the system curve, with shaft power and affinity-law scaling.
Open instrumentPump Power Calculator
Hydraulic power, shaft power and motor input for a pump from flow, head and efficiency, plus specific speed.
Open instrumentQuantum Monte Carlo Calculator
Run quantum Monte Carlo estimates for many-body systems.
Open instrumentQuantum Tunneling Calculator
Compute quantum tunneling probability through a potential barrier.
Open instrumentRadiation Calculator
Radiative exchange between two gray surfaces with the enclosure resistance network, radiation shields and a convection comparison.
Open instrumentRankine Cycle Calculator
Steam power cycle efficiency from the saturated steam table, with turbine and pump efficiencies, net work and exhaust quality.
Open instrumentRankine Regeneration Calculator
Rankine cycle with an open feedwater heater, showing the bleed fraction, the efficiency gain and the optimum extraction pressure.
Open instrumentRankine Reheat Calculator
Rankine cycle with reheat, showing the efficiency gain and the exhaust dryness improvement against the simple cycle.
Open instrumentRC Time Constant Calculator
Time constant, cutoff frequency, charge and discharge curves and energy stored for an RC circuit.
Open instrumentRebar Development Calculator
Rebar development length to ACI 318-19 with every adjustment factor, plus the Class A and Class B lap splice lengths.
Open instrumentRelativistic Orbital Precession Calculator
Compute relativistic orbital precession such as the perihelion shift.
Open instrumentRelief Valve Calculator
Pressure relief valve sizing to API 520 Part I for gas and liquid service, with the gas constant, the choked-flow check and the API 526 orifice.
Open instrumentResistor Color Code Calculator
Decode a 4-band or 5-band resistor into resistance and tolerance, or find the band colors for a target value.
Open instrumentResponse Surface Calculator
A rotatable central composite design, a least-squares quadratic fit, and the canonical analysis that classifies the stationary point.
Open instrumentRetaining Wall Calculator
Rankine active pressure from soil, surcharge and water, with overturning, sliding and bearing checks plus the stem design moment.
Open instrumentReynolds Number Calculator
Reynolds number for pipe or external flow, the resulting flow regime, and the Darcy friction factor by Colebrook.
Open instrumentRoom Load Calculator
Room cooling and heating load with every watt attributed: conduction, solar, people, lighting, equipment, ventilation and latent, plus supply airflow.
Open instrumentSample Size Calculator
Observations needed to detect a mean difference or estimate a proportion, with power and confidence.
Open instrumentSection Builder
Section properties from geometry: area, second moments, elastic and plastic moduli, radii of gyration, torsion and warping constants, and mass per metre.
Open instrumentSection Properties Calculator
Second moment of area, section modulus, radius of gyration and plastic modulus for rectangular, circular and hollow sections.
Open instrumentSeismic Base Shear Calculator
Base shear and seismic coefficient from SDS, SD1, R, Ie, period and weight, with the calculated, capped and minimum coefficients compared.
Open instrumentSeismic Detailing Calculator
Special moment frame detailing to ACI 318-19: beam proportions, confinement spacing, strong-column ratio and joint shear.
Open instrumentSeismic Response Calculator
Analyze a structure's seismic response to ground motion.
Open instrumentSeries & Parallel Resistance Calculator
Equivalent resistance, current, voltage and dissipation for three resistors in series or parallel.
Open instrumentService Load Calculator
Dwelling service load by the NEC standard method, with the Table 220.
Open instrumentShear Wall Calculator
In-plane shear strength of a reinforced concrete wall: the concrete term with axial load, the horizontal steel term, and the minimum reinforcement check.
Open instrumentShort-Circuit Calculator
Fault level at the end of a cable run from the transformer impedance and cable impedance, with peak current and the adiabatic cable size.
Open instrumentSlender Column Calculator
Second-order moment magnification and sway amplification for reinforced concrete columns.
Open instrumentSlope Stability Calculator
Slope stability by the simplified Bishop method with a search over slip circles, reporting the minimum factor of safety and the critical circle.
Open instrumentSnow Drift Calculator
Leeward snow drift height, width and surcharge for a roof step, evaluated in the published ASCE 7 form.
Open instrumentSnow Load Calculator
ASCE 7-22 roof snow load: exposure, thermal and importance factors, slope shedding, the 20Is minimum, rain-on-snow and leeward drift height.
Open instrumentSolar Panel Calculator
Size a PV array and battery bank for a daily energy demand, with system losses, yield and simple payback.
Open instrumentSoot and Ash Radiation Calculator
Radiative emissivity and flux from a sooty flame, combining WSGG gas bands with soot and ash absorption coefficients.
Open instrumentSpace Truss Calculator
A three-dimensional pin-jointed truss solved with three degrees of freedom per node: square pyramid, member forces, reactions and apex deflection.
Open instrumentSpring Rate Calculator
Compression spring rate from wire and coil geometry, with Wahl-corrected shear stress, deflection and solid height at a working load.
Open instrumentSteam Pipe Calculator
Steam pipe sizing on velocity from the saturated steam table, with the required bore, the nominal size and the actual velocity.
Open instrumentSteam Trap Calculator
Steam trap orifice and capacity with the flash fraction and the return line size, sized on the flash rather than the condensate.
Open instrumentSteel Connection Design
Bolted shear connection against every limit state: bolt shear, bearing, tearout, block shear and slip resistance, with the governing state named.
Open instrumentSteel Fire Resistance Check
Critical temperature and time to failure for unprotected steel in the ISO 834 standard fire.
Open instrumentSteel Member Code Check
Check a steel I-section for bending, shear, compression and deflection to AISC 360-22 LRFD or EN 1993-1-1, with the governing utilisation and every formula shown.
Open instrumentSteel Section Database
AISC Shapes Database v15.
Open instrumentStorage Tank Shell
API 650 §5.
Open instrumentStormwater Runoff Calculator
Stormwater peak flow by the rational method and runoff volume by the NRCS curve number, with time of concentration from Kirpich.
Open instrumentStructural Dynamics Calculator
Solve multi-degree-of-freedom structural dynamics and modal response.
Open instrumentStructural Reliability Calculator
Reliability index and failure probability by FORM, with direction cosines, the design point and a Monte Carlo check.
Open instrumentThermal Bridge Calculator
H = ψ·L·ΔT; ψ from the detail, ISO 10211 or the manufacturer.
Open instrumentThermal Expansion Calculator
Length change from a temperature rise, plus the restrained thermal stress and strain for common materials.
Open instrumentThree-Phase Power Calculator
Real, reactive and apparent power for a balanced three-phase load from line voltage, current and power factor.
Open instrumentTimber Beam Calculator
NDS allowable-stress beam design: the adjustment chain, beam stability, bending, shear, deflection and the governing allowable load.
Open instrumentTolerance Stack-Up Calculator
Worst-case and root-sum-square tolerance stack-up across five components, with variance shares and the tightening factor.
Open instrumentTorsional Vibration
Free–free torsional mode of a uniform shaft.
Open instrumentTransformer Sizing Calculator
Size a transformer from load kW and power factor, with standard ratings, primary and secondary currents, regulation, losses and fault current.
Open instrumentTransient Heat Calculator
Transient heating and cooling time, with the Biot check, the lumped time constant and the one-term approximation.
Open instrumentTruss Analysis Calculator
Solve a Warren, Pratt or Howe roof truss by the direct stiffness method: every member force, reaction and deflection, with equilibrium checked.
Open instrumentTurbulent Boundary Layer Calculator
Analyze turbulent boundary-layer profiles and spectral closure.
Open instrumentTwo-Phase Flow Calculator
Two-phase pressure gradient by the separated-flow and homogeneous models, with the Martinelli parameter, void fraction and regime.
Open instrumentTwo-Phase Relief Calculator
Two-phase relief valve sizing by the API 520 omega method for flashing service, with the critical mass flux and a liquid-only comparison.
Open instrumentTwo-Way ANOVA Calculator
Two-way ANOVA on a 2×2 design with interaction, F ratios and p-values.
Open instrumentTwo-Way Slab Calculator
Static moment, panel moments, the column-strip share and the punching check at the column for a two-way slab.
Open instrumentUnit Converter
Convert length, mass, temperature, volume, speed, pressure, energy and data units instantly.
Open instrumentVibration Calculator
Analyze oscillatory and kinetic vibration of mechanical systems.
Open instrumentVoltage Divider Calculator
Output voltage, current and power for a two-resistor divider, with load-resistance error and the divider ratio.
Open instrumentVoltage Drop Calculator
Conductor voltage drop and end-of-line voltage for a run, per common wiring standards.
Open instrumentWaveguide Attenuation Calculator
Compute electromagnetic waveguide attenuation and propagation modes.
Open instrumentWeibull Reliability Calculator
Survival probability, hazard rate, MTBF and B10 life from Weibull shape and scale parameters.
Open instrumentWire Gauge Calculator
Convert AWG to conductor area and resistance, check ampacity against a load current, and compute run voltage drop.
Open instrumentFinancial
179 calculators401(k) Calculator
Project a 401(k) balance with salary growth, contribution rate and employer match, and see the match value you would leave on the table.
Open instrument529 College Savings Calculator
Project a 529 plan to enrolment, with the state deduction, the tax-free growth and the cost of a non-qualified withdrawal.
Open instrumentAlternative Minimum Tax Calculator
AMT exemption, phase-out, 26/28% tentative tax and the excess over regular tax for 2026.
Open instrumentAmerican Option Calculator
Price American options by least-squares Monte Carlo (Longstaff-Schwartz).
Open instrumentAmortization Calculator
Full amortization schedule with month-by-month principal and interest breakdown.
Open instrumentAnnuity Calculator
Present and future value of an ordinary or due annuity, with payment growth, effective annual yield and the payout that a lump sum buys.
Open instrumentAPR Calculator
APR from the note rate, term and closing costs, solved from the discounted payment stream, with the monthly payment and total cost of credit.
Open instrumentAPY Calculator
Convert a nominal rate into the effective annual rate for any compounding frequency, including continuous compounding.
Open instrumentARM Calculator
Adjustable-rate mortgage payments at the teaser rate, the first capped reset and the lifetime ceiling, with the payment jump.
Open instrumentAsset Location Calculator
After-tax future value in a taxable versus a tax-deferred account.
Open instrumentAuto Lease Calculator
Lease payment split into depreciation and rent, money factor converted to APR, total lease cost and a like-for-like comparison with buying.
Open instrumentAuto Loan Calculator
Car loan payment including sales tax, trade-in credit, down payment and dealer fees, with total cost of ownership over the term.
Open instrumentAutocallable Note Calculator
Monte Carlo pricing for a Phoenix autocallable with coupon memory, the fair coupon and the autocall distribution.
Open instrumentAverage Return Calculator
Arithmetic average against compound annual growth.
Open instrumentBlack-Litterman Portfolio Calculator
Blend market equilibrium with your own views to set portfolio weights (Black-Litterman).
Open instrumentBlack-Scholes Options Calculator
Price European call and put options with the Black-Scholes model.
Open instrumentBoat Loan Calculator
Level payment amortisation at a fixed rate.
Open instrumentBond Duration Calculator
Price a coupon bond from its yield, then compute Macaulay and modified duration, convexity and DV01.
Open instrumentBond Yield Calculator
Compute a bond's yield, price and duration.
Open instrumentBreak-Even Calculator
Find the unit volume and revenue needed to cover fixed costs, with contribution margin and margin of safety at your planned output.
Open instrumentBudget Calculator
Split take-home pay into needs, wants and savings, compare with the 50/30/20 benchmark, and see unassigned income explicitly.
Open instrumentBurn Rate and Runway
Runway in months, the date cash runs out, the break-even month and the month-by-month cash curve with revenue and expense growth.
Open instrumentBusiness Loan Calculator
Level amortisation plus the DSCR coverage test.
Open instrumentCAGR Calculator
Convert a start value, end value and holding period into a compound annual growth rate, with total growth and doubling time.
Open instrumentCanadian Mortgage Calculator
Canadian convention: nominal rate compounded semi-annually, paid monthly.
Open instrumentCap Rate Calculator
Cap rate, DSCR, cash-on-cash and gross rent multiplier for a rental deal, with the loan terms that turn an unlevered yield into a levered one.
Open instrumentCap Table Calculator
Model a priced round with a pre-money option pool: price per share, shares issued, and every holder’s post-money ownership and paper value.
Open instrumentCapital Allocation Calculator
Allocate capital across assets to balance risk and return.
Open instrumentCapital Gains Tax Calculator
Long-term capital gains tax with 0/15/20% bracket stacking on ordinary income and the 3.
Open instrumentCaplet Bootstrap Calculator
Bootstrap caplet volatilities from a cap strip, with the forward vol curve and the repricing check.
Open instrumentCAPM Calculator
Estimate an asset's expected return from its beta with the Capital Asset Pricing Model.
Open instrumentCash Back vs Low Interest
Both offers compared over the same term and price.
Open instrumentCD Calculator
Certificate of deposit maturity value and APY from the nominal rate, compounding frequency and term, with the early-withdrawal penalty.
Open instrumentCDO Tranche Calculator
CDO tranche expected loss and wipe-out probability under the one-factor Gaussian copula, with base correlation.
Open instrumentCharitable Trust Calculator
Charitable remainder and lead trust mechanics: §7520 valuation, the deduction or taxable gift, and the income, charity and family split.
Open instrumentCIR Interest Rate Calculator
Model short-term interest rates with the Cox-Ingersoll-Ross process.
Open instrumentClosing Costs Calculator
Itemised buyer and seller closing costs, cash to close and the round-trip transaction friction a property has to clear.
Open instrumentCollege Cost Calculator
Cost inflation compounding to the first year of study.
Open instrumentCommission Calculator
Tiered commission and the effective rate on the sale.
Open instrumentCommodity Mean-Reversion Calculator
Model mean-reverting commodity prices with the Schwartz model.
Open instrumentCompound Interest Calculator
Project savings growth with contributions, compounding frequency, fees and taxes.
Open instrumentConstruction Loan Calculator
Interest reserve, loan-to-cost and equity gap for a drawn construction facility.
Open instrumentCorporate Debt Calculator
Analyze corporate debt financing cost and structure.
Open instrumentCovenant Headroom
Net leverage, interest cover and DSCR against their covenant limits, with the headroom in ratio units and in EBITDA.
Open instrumentCredit Card Payoff Calculator
Time and cost to clear a credit card balance at a given payment, or the payment to hit a deadline.
Open instrumentCredit Default Swap (CDS) Calculator
Price a credit default swap from its hazard (default) rate.
Open instrumentCredit Risk Capital Calculator
Credit valuation adjustment and regulatory capital from the same exposure.
Open instrumentCurrency Converter
Convert between USD, EUR, GBP, JPY and CHF at the ECB daily reference rate, with the bank fee shown separately.
Open instrumentCVA Hedge and Capital Calculator
CVA from the CDS curve, the hedge notional that neutralises its spread sensitivity, and Basel internal-model capital for the same exposure.
Open instrumentDCF Valuation Calculator
Value a company or project from its discounted future cash flows.
Open instrumentDebt Consolidation Calculator
Compare consolidating several debts against keeping them, at the same monthly outlay, with the interest saved and the fee break-even.
Open instrumentDebt Sculpting
Debt capacity as the present value of the maximum annual service.
Open instrumentDebt Snowball Calculator
Compare snowball (smallest balance first) and avalanche (highest rate first) payoff orders across multiple debts with one extra payment.
Open instrumentDebt-to-Income Calculator
Front-end and back-end debt-to-income ratios against the 28/36/43/50 thresholds, with the maximum housing payment and indicative loan capacity.
Open instrumentDepreciation Calculator
Build a depreciation schedule under straight-line, double-declining-balance or sum-of-years-digits, with book value by year.
Open instrumentDevelopment Feasibility
Residual land value after build cost, fees and profit.
Open instrumentDiscount Calculator
Apply one or two stacked discounts plus sales tax, and see the true effective markdown rather than the advertised percentages.
Open instrumentDistribution Waterfall
Whole-fund distribution waterfall: return of capital, preferred return, GP catch-up and the carried-interest split.
Open instrumentDividend Reinvestment Calculator
Dividend reinvestment modelled as a share count: income, the shares each dividend buys, and the value against taking the cash.
Open instrumentDown Payment Calculator
Time to reach a down payment target with monthly contributions, and the mortgage insurance cost at each LTV under the Homeowners Protection Act.
Open instrumentDSCR Calculator
Debt service coverage ratio, supported debt service at a covenant, and the loan that payment supports.
Open instrumentDual-Curve Swap Calculator
Price a swap with a term projection curve and an OIS discount curve, with the collateral basis against single-curve pricing.
Open instrumentDynasty Trust Calculator
Generation-skipping trust modelling across generations, with the inclusion ratio, GST on distributions and the state tax that survives the structure.
Open instrumentEmergency Fund Calculator
Months of cover your savings buy, the balance a real safety net needs, and how long a monthly deposit takes to close the gap.
Open instrumentEstate Tax Calculator
Federal estate tax from gross estate, deductions, exemption and portability, with annual gifting capacity.
Open instrumentExpected Loss Calculator
Expected loss from PD, LGD and EAD, with the loss rate and allowance buffer.
Open instrumentExpected Shortfall Calculator
Expected shortfall at any confidence for normal and fat-tailed books, against the 99% VaR, with the Basel 97.
Open instrumentFederal Income Tax Calculator
2025 federal income tax from gross income, pre-tax deductions and filing status, with the bracket table, effective rate and marginal rate.
Open instrumentFHA Loan Calculator
FHA monthly payment with the 1.
Open instrumentForex & Currency Calculator
Convert currencies and gauge cross-border FX liquidity.
Open instrumentFRTB GIRR Calculator
Weighted sensitivities aggregated with the GIRR correlation function, with the correlation matrix and the hedging benefit shown.
Open instrumentFund Metrics Calculator
TVPI, DPI, RVPI and net IRR for a fund or portfolio, with the IRR solved on dated cash flows rather than approximated.
Open instrumentFuture Value Calculator
What a lump sum and monthly contributions grow to.
Open instrumentGARCH Volatility Calculator
Forecast volatility with a GARCH model.
Open instrumentGDP & Macroeconomics Calculator
Estimate macroeconomic output and GDP components.
Open instrumentGift Tax Calculator
Federal gift tax with the $19,000 annual exclusion, the $13.
Open instrumentGRAT and IDGT Sale Calculator
Estate freeze structures compared: GRAT annuity and remainder against a sale to a defective grantor trust with a note at the AFR.
Open instrumentGST and Charitable Estate Calculator
Generation-skipping transfer tax, charitable bequest savings and trust administration drag.
Open instrumentHELOC Calculator
HELOC payment during the interest-only draw and the amortising repayment, with total interest and the payment step-up.
Open instrumentHeston Volatility Calculator
Price options under Heston stochastic volatility.
Open instrumentHJM Interest Rate Calculator
Model the forward interest-rate curve with the Heath-Jarrow-Morton framework.
Open instrumentHome Equity Loan Calculator
Home equity loan payment and combined LTV, with the borrowing capacity at the lender limit and a HELOC comparison.
Open instrumentHome Sale Proceeds Calculator
Net proceeds from a home sale after commission, the loan payoff and the §121 exclusion, with the capital-gains tax on any excess.
Open instrumentHouse Affordability Calculator
The home price your income, debts and down payment support, with DTI limits made explicit.
Open instrumentHousehold Cash Flow Plan
Year-by-year inflows and outflows across a household plan, with the home sale as a cash event.
Open instrumentHousehold Financial Plan
A multi-year household projection: income, spending, tax, three account buckets and drawdown on one timeline.
Open instrumentHSA Calculator
Project a health savings account against the IRS limit, with the income tax and payroll tax avoided and the after-tax value of the balance.
Open instrumentInflation Calculator
Convert nominal amounts into real purchasing power, and find the nominal return needed to beat inflation after tax.
Open instrumentInterest Rate Calculator
Solve the annual rate implied by a loan amount, a monthly payment and a term, by bisection on the amortising balance equation.
Open instrumentInterest Rate Swap Calculator
Annual net payment, NPV and break-even floating rate for a fixed-for-floating interest rate swap.
Open instrumentIRMAA and Medicare Premium Calculator
2026 Part B and Part D IRMAA tiers, the annual cost and the distance to the next cliff.
Open instrumentIRR Calculator
Find the internal rate of return of a cash-flow stream.
Open instrumentIRRBB Calculator
Interest-rate risk in the banking book: EVE, NII, the repricing gap and the Basel standardised scenarios.
Open instrumentJump-Diffusion Option Calculator
Price options with Merton jump-diffusion dynamics.
Open instrumentKelly Criterion Calculator
Growth-optimal stake from an edge, with the log-growth curve, fractional Kelly and the over-betting threshold.
Open instrumentLBO Calculator
Entry and exit multiples, debt package, equity cheque, MOIC and IRR for a leveraged buyout.
Open instrumentLife Insurance Needs
DIME: debt, income, mortgage, education, less existing assets.
Open instrumentLoan Payment Calculator
Monthly payment, total interest and full amortization schedule for any fixed-rate amortizing loan, with extra-payment payoff effects.
Open instrumentLocal Volatility Calculator
Dupire local volatility from a parametric implied surface, with the smile, the risk-neutral density and the local-vol grid.
Open instrumentLong-Term Care Cost
Inflated care costs against available assets and income.
Open instrumentM&A Accretion / Dilution
Pro forma EPS after synergies and financing cost.
Open instrumentMargin & Leverage Calculator
Calculate margin, leverage and liquidation levels for a position.
Open instrumentMarket Microstructure Calculator
Analyze high-frequency market microstructure signals.
Open instrumentMarkup & Margin Calculator
Convert between cost, selling price, markup on cost and gross margin on price, and see the profit per unit each way.
Open instrumentMarriage Penalty Calculator
Federal marriage penalty or bonus from the 2025 schedules, with the SALT cap that does not double and the income at which the penalty starts.
Open instrumentMBS Prepayment Calculator
Mortgage pool cash flows under the PSA prepayment model, with weighted average life, prepayment share and price at a discount rate.
Open instrumentMonte Carlo Simulation Calculator
Run Monte Carlo simulations of stochastic price paths.
Open instrumentMortgage Calculator
Monthly mortgage payment with taxes, insurance and HOA, plus the amortisation schedule, interest-to-principal split and rate sensitivity.
Open instrumentMortgage Payoff Calculator
See how extra monthly or one-time payments pay off your mortgage early and cut total interest.
Open instrumentMortgage Recast Calculator
Re-amortising the remaining balance over the original term.
Open instrumentMutual Fund Calculator
Fund growth net of the expense ratio, and what the fee costs.
Open instrumentNet Investment Income Tax
IRC §1411; thresholds are statutory and not indexed for inflation.
Open instrumentNet Worth Calculator
Build a personal balance sheet and read net worth alongside liquid net worth, leverage and liquidity share.
Open instrumentNPV Calculator
Discount a five-year cash-flow forecast to today: net present value, IRR, profitability index and discounted payback, with a sensitivity grid.
Open instrumentOption Pool Dilution
The pool is carved out before the round.
Open instrumentPayback Period Calculator
See how many years a project needs to repay its initial outlay, both on undiscounted and discounted cash flows, with interpolated fractions of a year.
Open instrumentPaycheck Calculator
Gross salary to take-home pay: federal brackets, social security, Medicare, state tax, pre-tax and post-tax deductions, per pay period.
Open instrumentPension Calculator
Project a defined-benefit pension's future payout.
Open instrumentPersonal Loan Calculator
Payment, total interest and the effect of an extra payment.
Open instrumentPMI Calculator
Monthly PMI from loan-to-value and rate, with the LTV path and the month automatic termination is reached.
Open instrumentPortfolio Optimization Calculator
Build the efficient frontier and optimize a portfolio (Markowitz mean-variance).
Open instrumentPresent Value Calculator
What a future amount is worth today at a discount rate.
Open instrumentProperty Pro Forma
Gross rent to NOI, cap rate, loan, cash-on-cash and DSCR for a rental property.
Open instrumentProperty Tax Calculator
Annual property tax from market value, assessment ratio, exemption and mill rate, with the monthly escrow and the effective rate.
Open instrumentPSLF Calculator
PSLF eligibility across all five rules, with the remaining payments, projected tax-free forgiveness and the cost of payments that did not qualify.
Open instrumentQBI Deduction (199A) Calculator
20% qualified business income deduction with the wage/property limit and the SSTB phase-out.
Open instrumentQuarterly Estimated Tax Calculator
Federal income and self-employment tax on the 2025 schedule, with the 90% and 100/110% safe harbours and the four quarterly instalments.
Open instrumentReal Estate Investment Calculator
Estimate rental yield and returns on a real-estate investment.
Open instrumentRefinance Calculator
Compare refinancing a loan against keeping your current one.
Open instrumentRegime-Switching Model Calculator
Model markets that switch between regimes (Hamilton Markov switching).
Open instrumentRent Affordability Calculator
How much rent you can afford under the HUD 30% threshold, the 40× landlord screen and the residual income method, with the binding rule identified.
Open instrumentRent vs Buy Calculator
Rent versus buy on net cost, with equity, appreciation, transaction costs and the opportunity cost of the down payment, and the year buying breaks even.
Open instrumentRetirement Calculator
Monte Carlo retirement projection with survival percentiles and market stress scenarios.
Open instrumentRetirement Plan Monte Carlo
Seeded Monte Carlo over the household plan: success rate, ending-balance percentiles and the effect of volatility.
Open instrumentRetirement Tax & Withdrawal
RMD, withdrawal order across taxable, tax-deferred and Roth accounts, 2025 federal brackets, taxable Social Security and the marginal cost of a Roth conversion.
Open instrumentRMD Calculator
Required minimum distributions year by year from the IRS Uniform Lifetime Table, with the SECURE 2.
Open instrumentROI Calculator
Net profit, return on investment and annualized ROI for any investment, with the cost base made explicit.
Open instrumentRoth IRA Calculator
Compare Roth and traditional IRA outcomes after tax, including contribution limits, growth and the tax rate at withdrawal.
Open instrumentRough Volatility Calculator
Model rough volatility with fractional Brownian motion.
Open instrumentRSU Calculator
Ordinary income at vest; flat supplemental withholding rate.
Open instrumentSABR Swaption Calculator
Price swaptions and build volatility smiles with the SABR model.
Open instrumentSalary to Hourly Calculator
Convert a salary to an hourly rate and back, with paid leave, holidays and overtime, reporting both the payslip rate and the rate per hour worked.
Open instrumentSales Tax Calculator
Add or extract US sales tax with state and local rates stacked, and split the tax by jurisdiction.
Open instrumentSavings Calculator
Compound growth of a savings balance with regular deposits, interest and inflation.
Open instrumentSavings Goal Calculator
Turn a target balance and a deadline into the monthly deposit required, after growing what you already have.
Open instrumentScenario DCF Valuation Calculator
Run best, base and worst-case DCF valuations side by side.
Open instrumentScenario Provision Calculator
Probability-weighted credit allowance across base, downturn and severe scenarios.
Open instrumentSelf-Employment Tax Calculator
Self-employment tax from net profit with the 92.
Open instrumentSequence-of-Returns Backtest
Replay a retirement plan against every 30-year window of real US equity returns since 1926: success rate, worst start year, drawdown and ending-balance spread.
Open instrumentSeries I Bond Calculator
Series I savings bond value from the fixed rate and semiannual inflation, with the Treasury composite-rate formula and the early-redemption penalty.
Open instrumentSharpe Ratio Calculator
Risk-adjusted performance for a return series: Sharpe, Sortino, Treynor and information ratio from annual return, volatility and drawdown.
Open instrumentSimple Interest Calculator
Simple interest on the original principal with no compounding, in years and months, with the daily accrual and the compound comparison.
Open instrumentSocial Security Claiming Calculator
Compare retired-worker claiming ages 62–70 using SSA birth-cohort full retirement ages, early reductions and delayed credits, with lifetime totals and break-even age.
Open instrumentState Estate Tax Calculator
Federal plus state estate tax, with valuation discounts and credit-shelter trust savings.
Open instrumentState Income Tax Calculator
State income tax on 2026 brackets for all 50 states and DC, with the standard deduction and marginal rate.
Open instrumentStudent Loan Calculator
Standard and extended student-loan repayment: monthly payment, total interest and the effect of extra monthly payments.
Open instrumentStudent Loan IDR Calculator
Income-driven repayment under IBR, PAYE, ICR and SAVE, with the forgiven balance, the tax on it and the total cost across plans.
Open instrumentStudent Loan Refinance Calculator
Compare refinancing student loans against the interest saved, with the PSLF and income-driven forgiveness forfeited by going private.
Open instrumentSwap Curve Calculator
Par curve interpolation, bootstrapped discount factors and swap NPV against the curve.
Open instrumentTax Return Analyzer (1040)
Build a 2026 federal return from income, gains, adjustments, deductions and credits, bracket by bracket.
Open instrumentTax-Loss Harvesting
Immediate tax saving and the time value of the deferral.
Open instrumentThree-Statement Model
Income statement, cash flow and balance sheet from one set of drivers.
Open instrumentTip Calculator
Tip on the pre-tax subtotal, total on the cheque, per-person split and the effective tip rate after tax.
Open instrumentTrade Execution Calculator
Plan optimal trade execution that balances cost against risk (Almgren-Chriss).
Open instrumentTraditional IRA Calculator
Traditional IRA deduction under the 2025 phase-out, with the after-tax value at retirement against the same outlay in a Roth.
Open instrumentTreasury Bill Calculator
Treasury bill price, discount and coupon-equivalent yield from the quoted discount rate and days to maturity.
Open instrumentTreasury Futures Hedge Calculator
Contracts needed to hedge a bond portfolio with Treasury futures, with residual exposure and rate sensitivity.
Open instrumentUK Income Tax Calculator
UK income tax, National Insurance and pension contributions, with the personal allowance taper and the 62% marginal band.
Open instrumentUK Mortgage Calculator
Repayment mortgage with a product fee.
Open instrumentUK VAT Calculator
UK VAT in both directions at the standard, reduced or zero rate, with the reclaimable cost and the registration threshold.
Open instrumentUnit Economics Calculator
LTV, CAC payback, LTV/CAC and net revenue retention from five inputs, with the churn sensitivity that shows why retention beats acquisition.
Open instrumentUnit Price Calculator
Compare packages of different sizes on price per unit, and price the quantity you actually need including leftover.
Open instrumentVA IRRRL Calculator
VA IRRRL payment saving and the 36-month recoupment test, with the 0.
Open instrumentVA Loan Calculator
VA mortgage payment with the 2.
Open instrumentValue at Risk (VaR) Calculator
Estimate Value at Risk and portfolio volatility.
Open instrumentVAT Calculator
Add or remove VAT or GST from a price, with the net, tax and gross amounts and the effective tax rate.
Open instrumentWACC Calculator
Blend after-tax cost of debt and CAPM cost of equity by capital structure to get the weighted average cost of capital used as a discount rate.
Open instrumentWorking Capital and Cash Cycle
Days inventory, days sales outstanding, days payable and the cash conversion cycle, with the cash the cycle ties up.
Open instrumentXVA Calculator
Funding, margin and capital valuation adjustments on one exposure profile, with and without a collateral agreement.
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