Sales tax calculator
Turn a shelf price into the amount you actually pay.
Total to pay
$108.00
| Price before tax | $100.00 |
| Sales tax | $8.00 |
| Total | $108.00 |
How sales tax is worked out
The maths is short: tax is the price multiplied by the rate, and the total is the price plus that tax. A $100 item at an 8% rate carries $8 of tax and costs $108 at the register. Working backwards from a receipt is the part people get wrong. You do not subtract 8% of the total; you divide the total by 1.08, because the tax was charged on the smaller before-tax price. This calculator has a mode for that direction too.
The rate is the part that varies. The United States has no national sales tax, so the rate on a purchase is a stack: a state rate, often a county rate, sometimes a city or district rate on top. Five states (Oregon, Montana, New Hampshire, Delaware and most of Alaska) charge no statewide sales tax at all, while combined rates in parts of states such as Tennessee, Louisiana and Arkansas run close to 10%. The rate also depends on what is being bought, since many states exempt groceries or charge clothing differently.
Because the exact rate turns on the street address of the purchase, this page asks you for the rate rather than guessing your location. Your receipt, the seller, or your state tax authority site will show the combined rate that applied. A state-by-state rate lookup, built from sourced state data, is planned as a later addition to this calculator.
Frequently asked questions
How is sales tax calculated?
Multiply the price by the tax rate. A $100 item at an 8% rate carries $8 of tax and costs $108 in total. Combined rates usually stack a state rate with county and city rates, which is why the same item is taxed differently from one ZIP code to the next.
How do I work out the price before tax from a total?
Divide the total by one plus the rate. A $108 total at 8% divides to a $100 pre-tax price, because $100 plus 8% of itself is $108. This calculator's reverse mode does that division for you.
Which states have no statewide sales tax?
Delaware, Montana, New Hampshire and Oregon levy no statewide sales tax, and most of Alaska has none either, though some Alaskan localities do. Everywhere else, expect a combined state and local rate on most purchases.
Related calculators
Estimates only. Tax rules vary by state, county, city and product; this tool does the arithmetic, it is not tax advice.