Property Tax Reassessment Calculator accuracy and testing

Formula source

• New annual tax = reassessed value x tax rate. For mills, tax rate = mills / 1,000. Annual change = new annual tax - current annual tax. Monthly change = annual change / 12.

Test cases

Known limitations

• This calculator does not handle local exemptions, caps, assessment ratios, appeal outcomes, supplemental bills, special assessments, homestead rules, or state-specific reassessment laws. It is not tax or legal advice.

Assumptions

• All values, dates, rates, and tax assumptions are entered by the user.
• Calculations run locally in your browser and are not stored by Calwarden.
• Results are planning estimates only and are not tax, legal, accounting, lending, or investment advice.

Unit handling

• Current Annual Tax accepts values in $/yr.
• Reassessed Value accepts values in $.
• Rate Type accepts one of the configured options.
• Tax/Mill Rate accepts numeric values.
• Estimated Annual Tax Change is displayed as currency.
• Estimated New Annual Tax is displayed as currency.
• Estimated Monthly Change is displayed as currency.
• Effective Tax Rate is displayed as a percentage.

Rounding rules

• Number displays use up to 2 decimal places in the calculator UI.
• Currency outputs are displayed with standard US dollar formatting.
• Percent outputs are displayed with two decimal places.
• Input precision follows configured step values where provided.

Version history

Change log