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Percentage tool

Sales Tax Calculator

Calculate the tax amount and total from a pre-tax amount and the rate you choose.

Free · Private · Runs in your browser

Percentage tool

Enter an amount and tax rate

Apply the tax rate you choose. This tool does not identify jurisdictions or tax rules.

Your result will appear here after you submit valid values.

How the calculation works

Tax amount equals the pre-tax amount multiplied by the tax percentage divided by 100. Total equals the pre-tax amount plus the tax amount.

Conventions and boundaries

  • Rate: you supply the tax percentage; the tool does not look up a jurisdiction.
  • Amount: the result keeps the same currency or unit you entered, without identifying it.
  • Scope: exemptions, compound taxes, fees, shipping, and local tax rules are outside scope.

Version and verification

Calculation version 1.0.0; deterministic fixtures last verified 2026-08-20.