Sales Tax Calculator — Add or Remove Tax From a Price

Sales Tax Calculator

Works both ways: add tax to a price before tax, or pull the tax back out of a price that already includes it.

Every payment is the same, but the interest share shrinks as the principal share grows.

Adding tax is easy, removing it trips people up

Adding tax is a simple multiplication: a $100 item at 7% becomes $107. Removing tax is where mistakes happen. If a price of $121 already includes 21% VAT, the net price is not $121 minus 21%. That would give $95.59, which is wrong. The gross price represents 121% of the net, so you divide: 121 ÷ 1.21 = $100 exactly.

The reverse-tax formula

Net = Gross ÷ (1 + rate/100)

This matters whenever you have a receipt total and need the pre-tax figure for bookkeeping, or when a supplier quotes a price "including VAT" and you need the amount before tax for an invoice.

Rates vary widely

US sales tax is set by state and often by city or county on top, so a single national rate does not exist; common combined rates run from 0% to over 10%. EU VAT is set nationally, with standard rates mostly between 17% and 27% and reduced rates for essentials like food and books. Enter the exact rate that applies to your transaction rather than a rounded guess.

Tax-inclusive versus tax-exclusive pricing

US prices are usually shown before tax, with the tax added at the register. European prices are shown with VAT already included, which is why the shelf price is the price you pay. Choose "add" for the American convention and "remove" when you need to break down a European gross price. To take a discount off before tax, use the discount calculator first.

Frequently asked questions

How do I remove VAT from a price?

Divide the gross price by 1 plus the rate as a decimal. For 21% VAT, divide by 1.21. Subtracting the percentage from the gross gives a different, incorrect answer.

What is the difference between sales tax and VAT?

Sales tax is charged once, at the final sale to the consumer, and is common in the US. VAT is charged at each stage of production with businesses reclaiming what they paid, and is standard across the EU. For a consumer the end result looks similar.

Is sales tax calculated before or after a discount?

Almost always after the discount, on the reduced price you actually pay. Apply the discount first, then add tax to the result.

Why does my receipt total differ by a cent?

Rounding. Tax is often calculated per line and rounded, then summed, which can differ by a cent from tax calculated on the whole total. It is normal and unavoidable.