Sales Tax Calculator

Add sales tax to a price, or find the total with tax.

After-tax price

$129.90

Sales tax: $9.90
Before-tax price: $120
After-tax price: $130

Tax results are estimates. Your actual tax can differ based on credits, deductions, state and local rules. Consider a tax professional for your situation.

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How to calculate sales tax

After-tax = before-tax × (1 + rate/100)
Before-tax = after-tax ÷ (1 + rate/100)
Rate = (after-tax ÷ before-tax − 1) × 100

Worked example. After-tax price: $129.90.

Example inputs — Find: After-tax price; Before-tax price: $120; Sales tax rate: 8.25%. Starting values are illustrative.

From George Guju, founder of Calculyn · Educational calculator guidance, not professional advice.

How it works

Choose the missing price or rate and enter the other two values. Tax is added as a percentage of the pre-tax price. Removing tax requires division, not subtracting the same percentage from the final price.

Assumptions & limitations

Uses the tax year shown on the calculator.
Federal figures only unless a rate is entered.
Does not include every credit, deduction or local tax.

Formula and assumptions reviewed October 2026 by the Calculyn team. How we build our calculators

Frequently asked questions

How do I remove tax from a total?

Divide the total by (1 + rate). For $129.90 at 8.25%: 129.90 ÷ 1.0825 = $120.