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Sales Tax Calculator

Use this sales tax calculator to add sales tax to a price or extract the tax amount from a total that already includes tax. Enter any amount and tax rate to instantly see the before-tax price, tax amount, and after-tax total.

The price before tax if adding tax, or the total price including tax if extracting tax.

The combined sales tax rate including state and local taxes. US rates typically range from 0% to about 10.25% depending on state and locality.

Choose whether to add tax to a pretax price or extract/reverse-calculate the tax from a total that already includes tax.

This calculator handles two common scenarios: calculating the total price after adding sales tax to a pretax amount, and reverse-calculating the original price and tax from a tax-inclusive total. It works with any US state or local tax rate, or any custom rate you enter.

How It Works

Sales Tax Calculation

Add Tax: Total = Amount x (1 + Rate/100); Extract Tax: Before Tax = Total / (1 + Rate/100); Tax = Total - Before Tax

To add tax, multiply the pretax price by one plus the tax rate. To extract tax from a total, divide the total by one plus the tax rate to find the original price, then subtract to find the tax amount.

When adding tax, the tax amount is calculated by multiplying the pretax price by the tax rate divided by 100.

The total is the pretax price plus the tax amount.

When extracting tax, the before-tax amount is found by dividing the total by (1 + rate/100).

The tax amount is then the difference between the total and the before-tax amount.

The effective rate confirms the tax percentage relative to the before-tax amount.

Important Notes:

  • •This calculator uses a single flat tax rate. In practice, some items may be exempt from sales tax or taxed at a reduced rate depending on your state.
  • •Combined state and local tax rates vary widely across the US, from 0% in states with no sales tax to over 10% in some jurisdictions.
  • •This calculator does not account for tax exemptions, tax holidays, or special item categories.

Worked Example

A shopper wants to know the total cost of a $100 item in a jurisdiction with an 8.25% sales tax rate.

Inputs:

  • amount:100
  • tax Rate:8.25
  • calculation Mode:addTax

Result:

The sales tax on a $100 item at 8.25% is $8.25, making the total cost $108.25. If you instead had a receipt showing $108.25 total and wanted to extract the tax, the before-tax price would be $100.00 and the tax portion would be $8.25.

Who Is This Calculator For?

  • shoppers estimating totals
  • small business owners
  • online sellers
  • anyone budgeting for purchases

Frequently Asked Questions

Your local sales tax rate is the sum of your state rate plus any county and city taxes. You can find the exact rate for your address on your state's department of revenue website or by checking a recent receipt from a local store.
Reverse sales tax calculation finds the original pretax price from a total that already includes tax. You divide the total by (1 + tax rate) to separate the base price from the tax amount. This is useful for expense reporting, returns, and budgeting.
Five US states have no state-level sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon. However, some localities in Alaska do impose local sales taxes.
In most cases, yes. After the 2018 Supreme Court ruling in South Dakota v. Wayfair, most states require online retailers to collect sales tax if they have sufficient sales volume or transactions in the state. If tax is not collected, you may owe use tax.
No. Sales tax is collected only at the final point of sale to the consumer. Value Added Tax, or VAT, is collected at every stage of production and distribution. The US uses sales tax while most other countries use VAT.
It depends on the state. Many states exempt groceries from sales tax or tax them at a reduced rate. A smaller number of states exempt clothing. Check your state's rules for specific item exemptions.

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Last updated: April 11, 2026