Assessed Value Calculator Formula

Understand the math behind the assessed value calculator. Each variable explained with a worked example.

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Formulas Used

Assessed Value

assessed_value = assessed_val

Estimated Annual Tax

annual_tax = assessed_val / 1000 * tax_rate_per_thousand

Monthly Tax Equivalent

monthly_tax = (assessed_val / 1000 * tax_rate_per_thousand) / 12

Variables

VariableDescriptionDefault
market_valueFair Market Value(USD)400000
assessment_ratioAssessment Ratio(%)80
tax_rate_per_thousandTax Rate per $1,000(USD)12
assessed_valDerived value= market_value * assessment_ratio / 100calculated

How It Works

How Property Assessment Works

Local governments assess properties at a fraction of market value using an assessment ratio, then apply a tax rate to that assessed figure.

Formula

Assessed Value = Market Value x Assessment Ratio

Annual Tax = (Assessed Value / 1,000) x Tax Rate per $1,000

Notes

  • Assessment ratios vary by jurisdiction, commonly between 50% and 100%
  • Tax rates are often expressed as mills (per $1,000 of assessed value)
  • Homestead exemptions may further reduce taxable assessed value

    • Worked Example

    A home has a fair market value of $400,000 with an 80% assessment ratio and a tax rate of $12 per $1,000.

    market_value = 400000assessment_ratio = 80tax_rate_per_thousand = 12
    1. 01Assessed value: $400,000 x 80% = $320,000
    2. 02Annual tax: ($320,000 / 1,000) x $12 = $3,840
    3. 03Monthly tax equivalent: $3,840 / 12 = $320

    Ready to run the numbers?

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