How to use
- Choose Add tax to start from a price before tax, or Remove tax to start from a total that already includes tax.
- Enter the amount and the sales tax rate. You can look up your state’s rate in the table below.
- You get the total (or the price before tax), the tax amount and the formula used. Use Copy to copy just the amount.
How it is calculated
- Add tax: tax = price × rate, rounded to the nearest cent; total = price + tax.
- Remove tax: tax = total × rate ÷ (100 + rate), rounded to the nearest cent; price = total − tax.
Removing tax this way means the price and the tax always add back up to the total you entered.
Examples
| You enter | Rate | Sales tax | Result |
|---|---|---|---|
| $100.00 before tax | 8.875% | $8.88 | $108.88 total |
| $19.99 before tax | 6.25% | $1.25 | $21.24 total |
| $54.13 total | 8.25% | $4.13 | $50.00 before tax |
Why US prices don’t include tax
In the US, shelf prices and online prices are usually shown before sales tax, and the tax is added at the register or checkout. The rate depends on where the sale takes place, and it can change from one city or county to the next, so a single national price can’t include it. That is why it helps to work out the total before you buy, or to back the tax out of a receipt.
Sales tax is set by states and local governments, not the federal government. Each state also decides what is taxable: many exempt or reduce the tax on groceries and prescription drugs, and some exempt clothing.