Free tool
US Sales Tax Calculator
Add tax to a price or remove it from a total. Enter the combined rate, and the answer appears as you type.
Result
Tax addedEnter an amount and a tax rate.
The result updates as you type.
What this calculator does
A US sales tax calculation has three parts: the price before tax, the tax itself, and the final total. Depending on what you already know, you may need to work forwards or backwards. This page handles both directions with the same amount and rate fields.
Use Add tax when you have a price and need the tax-inclusive total. Use Remove tax when a receipt shows only the final amount and you need the original price. The result panel always shows all three figures, so you can check the math without redoing it.
The calculator uses the rate you enter. It is a straightforward arithmetic tool, not a tax service, and it does not decide whether a sale is taxable. No sign-up is needed, and the numbers you type never leave your browser.
How to use it
- Choose Add tax or Remove tax. The label on the amount field changes to match.
- Enter the amount. You can type a plain number such as
49.99or paste something like$1,234.56. Dollar signs and commas are ignored. - Enter the combined rate as a percentage, for example
8.25. Do not enter 0.0825, because that would be read as a fraction of one percent. - Read the result. The panel shows the price before tax, the tax amount, and the total. Use Copy result if you want the three lines on your clipboard.
The two formulas
Adding tax to a price
Tax equals the price multiplied by the rate, divided by 100. The total equals the price plus the tax.
tax = price x rate / 100
total = price + tax
Removing tax from a total
Divide the total by 1 plus the rate divided by 100. The tax is whatever is left after you subtract that pre-tax price from the total.
price = total / (1 + rate / 100)
tax = total - price
Worked examples
Adding tax to a small purchase
A book costs $49.99 and the combined rate is 8.25%. The tax is $4.12, so the customer pays $54.11. The unrounded tax is $4.124175, which is why the displayed figure is a cent lower than a quick mental estimate might suggest.
Taking tax out of a receipt total
A receipt shows $108.25 at 8.25%. Dividing by 1.0825 gives $100.00 before tax, and the tax portion is $8.25. Subtracting 8.25% from $108.25 instead would give $99.32, which is too low because the percentage should apply to the smaller pre-tax amount.
A larger invoice
An invoice for $1,250.00 at 7.5% carries $93.75 of tax and comes to $1,343.75. Large amounts follow the same formula; the calculator keeps the arithmetic in cents to avoid floating point drift.
Finding the right rate to enter
Sales tax in the United States is not one national rate. States set a base rate, and counties, cities, and special districts may add their own. The combined rate is the number that applies at the point of sale, and it can differ from one town to the next.
The most reliable figure is the rate printed on a recent receipt from the same seller, or the rate table published by the state revenue department. For an online sale, the rate often depends on where the buyer receives the goods, not where the seller is located. That rule is called destination sourcing, and many states use it for remote sales.
If you only know the state rate, enter that and treat the result as a lower bound. Adding a guessed local rate produces a number that looks precise but may be wrong.
What this calculator cannot do
Being clear about the limits is part of making the tool useful. This page does the arithmetic; it does not interpret tax law.
- It does not look up rates by address, city, county, or ZIP code.
- It does not decide whether you have nexus, or whether you are required to collect tax in a state. Thresholds are usually based on sales volume or transaction counts, and they differ by state.
- It does not know whether a particular product or service is taxable. Groceries, clothing, digital goods, and services are treated differently across states.
- It does not handle exemptions, resale certificates, tax holidays, or exempt customers.
- It does not choose between origin and destination sourcing, and it does not split a sale across jurisdictions.
- It does not apply a jurisdiction's specific rounding rule. It rounds the tax to the nearest cent.
- It does not prepare, file, or remit a tax return.
Privacy: the math stays on your device
Everything happens in the page you are looking at. The calculator does not send your amount or rate to a server, does not use an external API, and does not save your entries in local storage or a cookie.
The copy button writes to your clipboard only after you press it. Refreshing the page clears the fields. If you close the tab, the numbers are gone.
Troubleshooting
No result appears. Both fields need a value. The panel tells you which one is missing or invalid.
It says the entry is not a number. Remove letters and stray symbols. Digits, one decimal point, commas, a dollar sign, and a percent sign are accepted.
The total looks far too high. Check the mode and the rate. Entering 8.25 is correct for 8.25%. Entering 0.0825 tells the calculator to add 0.0825%, which is a very different number.
The rate is rejected. Rates above 100% and below 0% are blocked on purpose. No US combined sales tax rate comes close to 100%.
Copy does not work. Some browsers block clipboard access until you grant permission. You can still select the result text and copy it by hand.
Frequently asked questions
How do I add sales tax to a price?
Multiply the price by the tax rate divided by 100, then add that amount to the price. At 8.25%, a $49.99 item carries $4.12 of tax and comes to $54.11. The Add tax mode does this calculation for you.
How do I remove sales tax from a total?
Divide the tax-inclusive total by 1 plus the rate divided by 100. At 8.25%, $108.25 becomes $100.00 before tax. Do not simply subtract 8.25% from the total, because that gives a smaller and incorrect answer.
What is a combined sales tax rate?
It is the total of every sales tax that applies to one sale: the state rate plus any county, city, and special district rates. A receipt or invoice usually prints the combined figure. If it only shows the state rate, check the seller's location for local additions.
Does this calculator know the rate for my state or ZIP code?
No. It uses the rate you type in. Rate lookup needs an address database or a live service, and local rates change often. Your state revenue department or the seller's own rate table is the reliable source.
Which states have no statewide sales tax?
Oregon, Montana, New Hampshire, and Delaware have no statewide sales tax. Alaska also has no statewide sales tax, but some Alaska municipalities charge local sales tax. Local taxes can exist in other states too, so a zero state rate does not always mean a zero combined rate.
Why is the tax one cent different from my receipt?
Rounding is the usual reason. A store may round tax on each item, while this calculator rounds once on the amount you enter. A different local rate, a discount applied before tax, or a shipping charge can also explain a small gap.
Can I use this for invoices and business records?
You can use the result as a working estimate for an invoice or quote. It is not tax advice and it does not decide whether you must collect tax. Keep your own records and confirm your obligations with your state revenue department or an accountant.
Does it work for VAT or GST outside the United States?
The formulas work for any single percentage rate, but the rules are different. UK VAT is usually included in the displayed price, Canada combines GST with provincial taxes in some provinces, and Australia uses GST. Treat a non-US result as arithmetic only, not as a tax answer.
Are shipping charges and discounts taxed?
It depends on the state and on how the charge is described. Many sellers apply tax after a discount, and shipping is taxable in some states but not others. This calculator applies the rate to the amount you enter, so include or exclude those items before you start.
Is my data sent anywhere or stored?
No. The calculation runs in your browser. The page does not upload your numbers, save them, or send them to an analytics service. Refreshing or closing the page clears the inputs.
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This page is an arithmetic aid, not legal or tax advice. Last updated 1 November 2026.