In the US, the shelf price isn't the checkout price — sales tax is added at the register. This sales tax calculator adds tax to any price to show the tax amount and final total, and also works in reverse to extract the pre-tax price from a tax-inclusive receipt.
How to add sales tax to a price
Multiply the price by the rate as a decimal and add it on: total = price × (1 + rate ÷ 100). Worked example: a $249 purchase at an 8.25% combined rate adds $20.54 of tax, for a checkout total of $269.54.
How to remove sales tax (reverse calculation)
Working backwards from a receipt total, don't just subtract the percentage — divide instead: pre-tax = total ÷ (1 + rate ÷ 100). A $269.54 total at 8.25% means the item itself was $249. This reverse mode is invaluable for expense reports, bookkeeping, and comparing tax-inclusive vs tax-exclusive prices. Toggle the mode above to switch.
What rate should you use?
US sales tax combines state, county, city and special-district rates — the total ranges from 0% (Delaware, Montana, New Hampshire, Oregon) to roughly 10% in the highest-tax localities. Use the combined rate for the delivery or purchase location, which appears on receipts or your state revenue site. Outside the US, VAT/GST works similarly for the math — enter your rate and the same formulas apply.
Related everyday math
Buying something on sale? Apply the markdown first with the discount calculator, then add tax here for the true checkout price. Splitting the purchase? The tip & split calculator divides any total per person.
Why your rate depends on where you stand
US sales tax stacks: a state rate plus county, city, and special-district add-ons, so the true rate can change by crossing a street — statewide bases run roughly 4–7.25%, and combined local rates push some areas past 10%. The authoritative number for your address comes from your state's Department of Revenue site (search "[your state] sales tax rate lookup") or simply from any recent receipt: the rate printed there is the one to enter above.
The five states with no statewide sales tax
New Hampshire, Oregon, Montana, Alaska, and Delaware — the "NOMAD" states — charge no statewide sales tax. One asterisk: Alaska lets municipalities levy local sales taxes, so parts of it aren't truly tax-free, and every state applies excise taxes to specific goods (fuel, lodging, alcohol) regardless. If you're comparing a big purchase across state lines, enter each side's combined rate here and let the totals argue.