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  4. Sales Tax Calculator

Sales Tax Calculator

Solve any two of before-tax price, sales tax rate, and after-tax price — tax amount included.

Everyday money

  • ROI Calculator
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  • Sales Tax Calculator

How it works

Enter any two values among before-tax price, tax rate, and after-tax price. The calculator fills in the third plus the tax amount.

after-tax = before-tax × (1 + rate) · before-tax = after-tax / (1 + rate)

When to use

Use this tool when you need to: $100 at 10% tax adds $10 — you pay $110 total.

How to use this tool

  1. Enter your values in the fields above.
  2. Review the formula and any mode options for your problem.
  3. Read the result and the step-by-step solution.

$100 at 10% tax adds $10 — you pay $110 total.

Frequently asked questions

What is the Sales Tax Calculator?
Enter any two values among before-tax price, tax rate, and after-tax price. The calculator fills in the third plus the tax amount.
How do I use the Sales Tax Calculator?
Enter the required values, then calculate. The Sales Tax Calculator shows results, formulas, and step-by-step work when available. No account is required.
What formula does the Sales Tax Calculator use?
after-tax = before-tax × (1 + rate) · before-tax = after-tax / (1 + rate)

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Sales Tax Calculator

Compute before-tax price, sales tax rate, after-tax price, and tax amount — enter any two values and the rest are calculated.

Fill in any two fields — the third price and tax amount are calculated automatically.

Try an example

How it works

Any two values

Like calculator.net, provide any two of before-tax price, tax rate, and after-tax price. Tax amount is always after-tax minus before-tax.

Adding tax

When the shelf price excludes tax, multiply by 1 + rate. Example: $100 at 10% adds $10 tax for a $110 total.

Price includes tax

When the sticker price already includes tax, divide by 1 + rate to split the net and tax portions. $110 at 10% means $100 before tax and $10 tax.

U.S. sales tax notes

There is no federal sales tax in the U.S.; rates vary by state and locality from 0% to about 16%. Listed prices may be before or after tax depending on jurisdiction — know which you are entering.