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Sales Tax Calculator

Calculate sales tax and total price, or work backward from a total.

Total Price

108

Tax Amount

8

Pre-Tax Price

100

Related Guide

Sales Tax Calculator: Forward and Reverse Math Explained

Read Guide →

About This Tool

Free sales tax calculator — enter a price and tax rate to instantly calculate the tax amount and total price, or switch to reverse mode to work backward from a tax-included total to find the pre-tax price and tax amount. Sales tax rates vary widely by state, county, and city, so a single national rate rarely applies — this tool lets you enter whatever local rate applies to your calculation. The reverse mode is especially useful for receipts or invoices that only show a final total: enter that total and the known tax rate to see exactly how much was tax versus the original price. Runs entirely in your browser — nothing is uploaded or saved.

How to Use

  1. 1

    Enter the price and tax rate

    Type the pre-tax price and your local sales tax rate as a percentage.

  2. 2

    See tax and total

    View the tax amount and the final total price instantly.

  3. 3

    Switch to reverse mode if needed

    Enter a tax-included total instead to back-calculate the pre-tax price and tax amount.

Frequently Asked Questions

How is sales tax calculated?+
Tax Amount = Price × (Tax Rate / 100). Total Price = Price + Tax Amount. Reverse mode divides a tax-included total by (1 + Tax Rate / 100) to find the pre-tax price.
Why do sales tax rates vary so much by location?+
In many countries, sales tax is set at state, county, and city levels and stacked together, so the combined rate can differ significantly even between neighboring cities.
Can I use this for VAT instead of sales tax?+
Yes, the math is the same — VAT is also a percentage added to a base price, so entering your local VAT rate works identically to a sales tax rate.

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