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    ZorvLabs / Product packaging

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    All 372 calculators open without an account. 215 are complete on Free — nothing held back; 114 add professional depth, and 43 more add research-scale analysis.

    Individual workspaceLocal-first
    Packaging preview. Billing and entitlement verification are not connected.
    FreeAlways included

    Free

    Every one of the 372 calculators, core answer included. 215 are complete on Free — full formula, worked example and assumptions, no account.

    FreeNo account required
    • Complete core calculationThe full formula or solver, never a deliberately reduced answer.Available in the current page
    • Input validation and assumptionsBounds, units, warnings and assumptions stay visible.Available in the current page
    • Formula and worked methodFormula reference, worked example and stated limitations.Available in the current page
    • Result summaryThe key metrics and how to read them.Available in the current page
    • Basic chart or diagnosticA chart, diagram or diagnostic where the calculator has one.Available in the current page
    • Structured detail tableThe detail table, schedule preview and component rows the page renders.Available in the current page
    Available now — no account
    ProProfessional depth

    Pro

    Adds professional depth on 114 calculators: full schedules, regional and model inputs, and exports.

    PreviewBilling is not connected
    • Advanced domain inputsRegional, model, calibration and geometry controls already present on the page.Included today — not gated yet
    • CSV data exportCSV of the full result set.Included today — not gated yet
    • Company-branded reportA PDF built from the engine result, with your name, logo, accent and a cover.Included today — not gated yet
    • Summary PDF reportOne-page summary template.Included today — not gated yet
    • Detailed PDF reportStandard record template: inputs, results, checks, charts, derivation.Included today — not gated yet
    • Complete PDF bundleChecked submission template with the full derivation and provenance.Included today — not gated yet
    • Custom report template uploadUpload a slot map to match a firm’s own pack; sections reorder, rename and filter.Included today — not gated yet
    • Interactive step-by-step workingClause-cited derivation and a baseline diff. The plain computation-steps card stays free on every page that has one.Included today — not gated yet
    • Unit-aware input and outputAn SI/US bridge that converts labelled inputs at the boundary and leaves the engine unit-agnostic.Included today — not gated yet
    • Selectable code editionACI 318-14/19/22, AISC 360-16/22, ASCE 7-16/22, NEC 2017/2020/2023, NDS, IBC.Included today — not gated yet
    • Referenced data libraryShipped tables with source and edition: rebar, ampacity, resistance, pipe, bolts, air.Included today — not gated yet
    • Saved projectsNamed projects with an append-only revision history.Included today — not gated yet
    • Revision historyEvery revision kept, diffable and restorable.Included today — not gated yet
    • Linked calculationsOne calculation’s output resolved into another’s input, with cycle detection.Included today — not gated yet
    • Template library and custom defaultsFirm input defaults, so two engineers start from the same assumptions.Included today — not gated yet
    • Baseline versus scenariosRun every saved revision and tabulate the metrics.Included today — not gated yet
    • Tax estimation2026 federal brackets, deductions, capital gains, NIIT and Social Security inclusion.Included today — not gated yet
    • Withdrawal sequencingPro-rata, taxable-first and bracket-fill, compared by after-tax terminal wealth.Included today — not gated yet
    • Roth conversion optimizerConversion sizing against a target bracket, with RMD relief and heir rates.Included today — not gated yet
    • Estate and legacyFederal estate tax, basis step-up and IRD on an inherited IRA.Included today — not gated yet
    • International presetsUS, UK, CA, AU, DE and IN, each labelled official or indicative.Included today — not gated yet
    • Structured research protocolStructured question, hypothesis, outcome and analysis plan attached to each cross-calculator study.Included today — not gated yet
    Included now · gated with billing
    UltraResearch scale

    Ultra

    Adds research-scale analysis on 43 calculators: sensitivity sweeps, seeded simulation, surface views and portable cross-calculator workspaces.

    PreviewBilling is not connected
    • Local sensitivity sweepLocal sweeps across the parameters that change the decision.Included today — not gated yet
    • Local Monte Carlo analysisSeeded simulation on the calculators that model uncertainty.Included today — not gated yet
    • Historical backtestingSequence-of-returns backtesting against market history.Included today — not gated yet
    • Larger or batched local runsBatch runs across named scenarios.Included today — not gated yet
    • Local worker computeHeavy solvers and simulation off the main thread.Included today — not gated yet
    • Reusable workspace bundleCross-calculator research bundles with saved inputs, native outputs, method provenance and portable JSON.Included today — not gated yet
    • Pre-run protocol snapshot and integrity checkFreeze a pre-run protocol and assumptions into a portable snapshot; verify its SHA-256 digest after handoff.Included today — not gated yet
    • Programmatic accessOne JSON endpoint per calculator, with an OpenAPI 3.1 document generated from the catalog.Included today — not gated yet
    • Spreadsheet integrationA sideloadable task pane plus a workbook that posts the sheet and writes the result back.Included today — not gated yet
    • Assistant over verified calculationsAn assistant that runs the verified engines and shows the computation, never a generated formula.Included today — not gated yet
    • Team seats and rolesTen seats included; roles for owner, admin, engineer, reviewer and client.Included today — not gated yet
    • Advisor workspaceClients, plans and a practice dashboard over the same project store.Included today — not gated yet
    • Advisor and client workspaceA client-facing view of sealed reports.Included today — not gated yet
    Included now · gated with billing
    Local by default

    Calculations stay in the browser. No public or cloud share is created by this panel; a future share flow must be explicit and show exactly what state leaves the device.

    Notes: Billing and entitlement verification are not connected, so nothing on this page is enforced yet. Calculations run locally; cloud sharing stays optional and explicit. Projects, revisions, templates and the team model are stored on this device until an account layer exists.

    Enforcement: not-configured

    PLANS / PRICE AND SCOPE

    What each plan costs, and what it adds.

    Free — $0

    Every calculator, complete, without an account.

    • All 372 calculators: inputs, full engine, metrics, a chart, the detail table, the formula and the worked example
    • Runs entirely in the browser — nothing is uploaded, no account, no worker
    • One local working project and five local snapshots per calculator
    • Print the page; the calculation is never reduced to sell an upgrade

    No account, nothing uploaded, no storage

    Pro — $15/mo

    The record, the derivation and the report.

    • Branded PDF reports generated from the engine result, with a cover, your logo and a seal
    • Step-by-step derivation with clause and formula references
    • Code edition selection: ACI 318-14/19/22, AISC 360-16/22, ASCE 7-16/22, NEC 2017/2020/2023
    • Units carried through input and output, with an SI/US bridge

    $129/yr (10.75/mo, save 28%) · 1 seat · 4 MB local project storage

    Ultra — $49/mo

    Compute, integration and a team.

    • Everything in Pro
    • Worker compute: Monte Carlo, parametric sweeps and batch runs
    • API access and an MCP server over every headless calculator
    • Excel add-in package and a generated Python client

    $449/yr (37.42/mo, save 24%) · 10 seats · 16 MB local project storage

    14-day trial and a 30-day money-back guarantee, matching the terms Calcs.com offers. Billing is not connected in this build. Every capability below ships today; the plan that owns it is packaging until checkout exists, and nothing is enforced at runtime.

    MARKET / WHAT THE OTHERS CHARGE

    Calcs.com Basic

    $66/mo — Library depth only; branded PDF on every plan.

    Calcs.com Ultimate

    $124/mo — Adds custom PDF uploads and priority support.

    CalcTree Business

    $34/user/mo — Linking, API, Excel add-in, unlimited reports.

    ProjectionLab Premium

    $129/yr — Tax optimisation, withdrawal strategies, estate.

    ProjectionLab Pro

    $549/yr — Client management, 10 seats.

    PTC Mathcad Prime

    Several hundred/yr — Units and programming; free tier is watermarked.

    COMPARISON / TRANSPARENT SCOPE

    What changes, and what never does.

    Every capability listed below ships today. Billing and authentication are not connected, so the plan that owns a capability is packaging rather than a runtime gate — the calculation itself is never withheld.

    CapabilityFreeProUltra
    Core answerFull formula, worked example, assumptionsSame — never reduced to sell an upgradeSame
    Inputs and domain controlsCore inputsRegional, model, calibration and geometry controlsSame as Pro
    Schedules, tables and diagnosticsThe detail table and a chart on every page that has oneFull ledgers and component schedules on the pages that carry themPlus surface and field views
    Scenarios and sensitivity1 saved scenario10 scenariosUnlimited scenarios · 500-point sweep
    Simulation and uncertaintyNot includedNot included500,000 Monte Carlo paths
    Reports and exportsPrint the page. No download.Branded PDF built from the engine result · four templates · custom slot map · CSVEverything in Pro, plus the API and the Excel add-in
    Export formatsPrintCSV (full result set) · Print · PDF reportCSV (full result set) · Print · PDF bundle · Portable state (JSON)
    Derivation and code depthThe governing equation and the worked exampleNumbered derivation with clause references · ACI 318, AISC 360, ASCE 7, NEC editions · SI/US unit bridge · referenced data tablesSame, with a sealed-calculation package and a printable derivation
    PersistenceOne working project · five local snapshots100 projects · 40 revisions each · append-only history with diffsUnlimited projects · 250 revisions each · team projects
    CompositionOne calculation at a timeLoad linking with cycle detection · firm templates · scenario comparisonUnlimited linking · batch composition across a practice
    Local history and research workspace5 runs · 1 local workspace100 runs · 10 local workspaces1,000 runs · unlimited workspaces · larger model batches
    Compute and integrationA single deterministic passSame — heavy compute is the Ultra step500,000 Monte Carlo paths · sweeps · batch · JSON API · MCP · Excel · Python
    Collaboration——Ten seats · five roles · advisor workspace with a client dashboard
    Study design and reproducibilityCapture inputs, outputs, and short research notesStructured question, hypothesis, outcome, and analysis planFreeze the pre-run plan and assumptions; verify its SHA-256 digest after handoff

    STAGES / WHAT IS GATED

    Inputs, model and presentation are never gated.

    Every calculator is split into eight stages. The first three stay open on every plan — a paid tier never changes what the engine computes or how the result is drawn. What it owns is the record around the answer.

    StageFreeProUltra
    Inputs and validationIncludedIncludedIncluded
    The engineIncludedIncludedIncluded
    DerivationFirst step onlyIncludedIncluded
    Charts and tablesIncludedIncludedIncluded
    Saved workNot includedIncludedIncluded
    ScenariosNot includedIncludedIncluded
    ExportNot includedIncludedIncluded
    Heavy computeNot includedNot includedIncluded

    IMPLEMENTATION PRINCIPLES

    Local by default. Explicit by design.

    Free stays useful

    Inputs, validation, the complete core calculation, essential outputs, and a basic diagnostic remain available without an account.

    Pro reflects reality

    Advanced controls are packaged only when the audited page already has them or they are clearly part of its domain workflow.

    Ultra earns its name

    Simulation, sensitivity and stress scale up where extra analysis changes a decision. Ultra adds frozen pre-run plans and integrity checks to Pro’s structured study protocol. Capacity targets are not enforced until billing connects.

    Sharing is opt-in

    A plain calculator URL is not called a saved calculation. Portable or public state will explain what leaves the device before it does.

    REGISTRY / DOCUMENTED CAPABILITIES

    The registry defines 50 capability IDs and assigns every calculator to a depth plan: 215 are complete on Free, 114 add Pro depth, and 43 of those add Ultra depth. All 372 remain fully usable while billing verification is intentionally unconfigured.