Property tax calculator
Property tax is not a percentage of what you paid for the house. It is a mill rate applied to an assessed value that may be a fraction of market value, minus any exemption. This engine walks market value → assessed value → taxable value → bill, and reports the effective rate so two jurisdictions can be compared honestly.
| Step | Amount |
|---|---|
| Market value | $400,000 |
| Assessed value (100%) | $400,000 |
| Less exemption | $0.00 |
| Taxable value | $400,000 |
| Tax at 12.00 mills | $4,800 |
A mill is one dollar per thousand dollars of taxable value.
assessed = market × ratio · Assessment ratios vary by jurisdiction and are often below 100%.
max(0, assessed − exemption) · Homestead and veteran exemptions reduce the base.
tax = taxable × mills / 1000 · One mill is $1 per $1,000 of taxable value.
tax / market · Lets you compare jurisdictions with different assessment rules.
A clear path from inputs to results.
Property tax is a mill rate applied to an assessed value, and the assessed value is often a fraction of market value. This calculator walks market value → assessed value → taxable value → annual bill, then reports the effective rate so two jurisdictions can be compared on the same basis.
How to use
- Enter the market value of the property.
- Set the assessment ratio from your jurisdiction.
- Subtract any homestead or other exemption.
- Enter the total mill rate from the tax notice.
The formula
Reference: Local assessment statutes; one mill equals $1 of tax per $1,000 of taxable value (IAAO, Property Appraisal and Assessment Administration).
Worked example
$400,000 home, 100% assessment, no exemption, 12 mills
- Market value $400,000.
- Assessment ratio 100%.
- No exemption.
- Mill rate 12.
- 1
Assessed value: 400,000 × 1.00 = $400,000.
- 2
Taxable value: 400,000 − 0 = $400,000.
- 3
Annual tax: 400,000 × 12 / 1,000 = $4,800.
- 4
Monthly escrow: 4,800 / 12 = $400.
- 5
Effective rate: 4,800 / 400,000 = 1.20% of market value.
Annual tax $4,800 · $400 a month · effective rate 1.20%.
Interpreting the result
The mill rate is the visible number, but the effective rate is the one that compares places. Two jurisdictions can both quote 12 mills and collect very different amounts if one assesses at 100% of market value and the other at 60%. The exemption matters just as much: a $50,000 homestead exemption at 12 mills is $600 a year, every year.
Assumptions & limitations
- The assessed value is computed from market value and the ratio you enter; it is not a prediction of a reassessment.
- Special assessments, delinquent amounts and non-ad-valorem charges are excluded.
- Mill rates change annually with levies and are applied to the taxable value on the notice.
- Appeals and caps on assessment growth are not modelled.
Frequently asked questions
What is a mill?
One dollar of tax per thousand dollars of taxable value. A 12-mill rate on $400,000 of taxable value is $4,800.
Does this include school tax?
Yes, if you include the school district millage in the total rate. Most notices list county, city, school and special-district levies separately.
Why is my assessed value lower than my market value?
Many jurisdictions assess at a statutory fraction of market value, and some cap annual increases. Use the ratio on your notice.
Will my bill rise if my value rises?
Usually, but not proportionally: exemptions, caps and rate changes all intervene. Change the market value input to see the sensitivity.
Methodology last reviewed 2026-10-21. Results are informational and not financial or engineering advice — see our disclaimer.