Comprehensive Guide
Learn more in our Personal Finance Guide.
How it works
Sales tax is a percentage levied by state and local governments on most retail purchases, added at the register on top of the listed price. This calculator works both directions. Forward, it adds a combined state-and-local rate to a pre-tax price to produce the checkout total. Backward, it strips the tax out of a tax-inclusive amount to recover the pre-tax price and the tax hidden inside it — and the extraction is division, not subtraction: dividing by one-plus-the-rate is what recovers the true base, while subtracting the percentage always leaves too much behind. There is no federal sales tax in the United States: statewide rates run from zero in Alaska, Delaware, Montana, New Hampshire and Oregon to 7.25% in California, before local additions push combined rates past 9% in some cities. Most states levy tax where the buyer receives the goods — destination-based — and online marketplaces now collect and remit it automatically in most cases, which is why cart totals match the calculator's forward mode.Formula
Add: total = price x (1 + rate/100) | Remove: pre-tax = total / (1 + rate/100)
Tips
- There is no US federal sales tax — the rate is whatever your state plus locality charges.
- Five states have no statewide sales tax — Alaska, Delaware, Montana, New Hampshire, Oregon — though Alaska's locals add their own.
- Most states are destination-based: the rate follows the delivery address, not the seller's.
- Removing tax means dividing by (1 + rate), never subtracting the percentage from the total.
- Groceries, prescriptions and clothing are exempt or reduced in many states — sticker rate rarely hits every line.
Frequently asked questions
How do I add sales tax to a price?
Multiply the price by (1 + rate). At 8.25%, an $89.99 item becomes $89.99 x 1.0825 = $97.41, of which $7.42 is tax. Use the combined state-plus-local rate for the delivery address to match a real checkout.
How do I remove sales tax from a total?
Divide the total by (1 + rate). A $108.25 receipt at 8.25% contains $108.25 / 1.0825 = $100.00 before tax and $8.25 of tax. Subtracting 8.25% from $108.25 gives the wrong answer — division is what back tax out correctly.
Which states have the highest sales tax?
California has the highest statewide rate at 7.25%; Tennessee, Louisiana, Arkansas and Washington carry some of the highest combined state-plus-local averages, with certain city combinations exceeding 9-10%. Several New England and Rocky Mountain states sit near zero.
Why do some states have no sales tax?
Alaska, Delaware, Montana, New Hampshire and Oregon raise revenue through other channels — income, property or resource taxes — and lean on sales-tax-free status as a retail draw. Local option taxes still exist, notably in Alaska, so the checkout rate is not always zero.
Do online purchases include sales tax?
Yes in nearly all cases since the South Dakota v. Wayfair decision and marketplace facilitator laws: large platforms collect and remit tax on your behalf at the destination rate. Small out-of-state sellers without nexus remain the rare exception, technically leaving use tax self-reporting to the buyer.