Finance calculator

Sales Tax Calculator

This sales tax calculator does both directions. Add tax to a price to get the checkout total, or reverse it, dropping in a total that already includes tax to find the pre-tax price and how much of it was tax. Add several items and it totals them first. Enter your combined rate and everything updates as you type.

  • Add tax
  • Reverse tax
  • Multiple items
  • Pre-tax price
  • Grand total

Last updated July 15, 2026 Enter your combined rate Reviewed by the Calcowa finance team

Direction

Prices are before tax; tax gets added at the total.

Item prices ($)
Grand total
$53.63

Pre-tax
$50.00
Sales tax
$3.63
Items
1
The math

The basics

How sales tax is calculated

Sales tax is a percentage added to the price of taxable goods at the point of sale. To add it, turn the rate into a decimal and multiply: an 8% rate is 0.08, so tax on a $40 item is $3.20 and the total is $43.20. The tricky direction is reversing it, when you have a receipt total that already includes tax and want the original price. For that you divide, not subtract, because the tax was a percentage of the smaller pre-tax figure, not the total.

Add: total = price × (1 + rate)  ·  Reverse: price = total ÷ (1 + rate)
Step by step

Backing tax out of a receipt total

Say a receipt reads $107.00 and you know the rate was 7%, and you want the pre-tax price for an expense report:

  1. 1

    Turn the rate into a multiplierA 7% rate means the total is 1.07 times the pre-tax price.

  2. 2

    Divide the total by the multiplier$107.00 ÷ 1.07 = $100.00, which is the price before tax.

  3. 3

    Find the tax portionSubtract the pre-tax price from the total: $107.00 − $100.00 = $7.00 of tax.

  4. 4

    Check itMultiply back: $100.00 × 1.07 = $107.00, so it balances.

Reference

State base sales tax rates

These are statewide base rates. Most cities and counties add local sales tax on top, so your combined rate at the register is often higher. Five states, Alaska, Delaware, Montana, New Hampshire, and Oregon, have no statewide sales tax, though some localities in Alaska do. Enter your full combined rate above for an exact figure.

StateBase rateStateBase rate
California7.25%Illinois6.25%
Texas6.25%Washington6.50%
New York4.00%Colorado2.90%
Florida6.00%Arizona5.60%

Working with a plain percentage instead? The percentage calculator handles any percent, and the discount calculator takes a percent off a price.

FAQ

Frequently asked questions

Multiply the price by the tax rate as a decimal, then add it to the price. At a 7% rate, tax on a $50 item is $50 × 0.07 = $3.50, so the total is $53.50. This sales tax calculator does that instantly, and it can also add up several items first, or work backwards from a total that already includes tax.

Divide the total by 1 plus the tax rate as a decimal. If a receipt shows $53.50 including 7% tax, the pre-tax price is $53.50 ÷ 1.07 = $50.00, which means $3.50 was tax. Switch this calculator to Remove tax and it does this reverse math for you, which most calculators and search boxes can't.

A tax-exclusive price is shown before tax, and the tax gets added at checkout, which is normal in the United States. A tax-inclusive price already has the tax baked in, common in many other countries. Use Add tax for exclusive prices and Remove tax for inclusive ones, and the calculator handles both.

It uses whatever rate you enter, so put in your full combined rate to include state, county, and city portions. The state rates in the table are base state rates only; most places add local taxes on top, so a listed 6% state rate might be 8% or 9% once local taxes are included. Check your exact combined rate with your state's revenue site.

Add a row for each item's price and the calculator totals them into a subtotal, then applies the tax rate once to the whole subtotal. That matches how a register works: it sums the taxable items, then charges tax on the sum. You'll see the subtotal, the tax, and the grand total update as you type.

Practically it's the same, because sales tax is a flat percentage. Whether you tax each item and add them, or add the items and tax the sum, you land on the same number. This calculator taxes the subtotal, which keeps rounding clean and matches most receipts.

Keep going

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Checking a receipt?

Add or reverse the tax above, or browse the full finance hub.

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