Sales Tax Calculator
This free sales tax calculator handles both directions of the US-style tax math.
How to use
- Choose the mode: add tax to a net price, or remove tax from a total.
- Enter the price and the combined sales tax rate.
- Read the tax amount, the other side of the split — instantly, on your device.
Frequently asked questions
How is tax added to a net price?
Tax = net price × rate ÷ 100, and the total is net + tax. Example: a 250 item at an 8% combined rate adds 20.00 of tax for a 270.00 total.
How does removing tax from a total work?
The tax inside a total is total × rate/(1 + rate) — not total × rate. For a 110 total at 10%, the tax is 110 × 10/110 = 10.00 and the net price is 100.00. Multiplying the total directly by the rate would wrongly give 11.00.
Which rate should I enter?
The combined rate that actually applies at the sale location: state + county + city + special district. The calculator does not bundle a rates database, so you always enter the rate yourself — that keeps it correct in every jurisdiction and immune to rate changes.
Does it handle VAT or reverse-inclusive pricing?
Yes for the arithmetic — VAT uses the same tax-out-of-total split when you start from a tax-inclusive amount. For a dedicated European-style tool with VAT terminology, see the VAT calculator.
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About this tool
This free sales tax calculator handles both directions of the US-style tax math. Forward mode takes a net price and a tax rate and gives you the tax amount plus the total you will actually pay at the register; reverse mode takes a receipt total and works backwards to show how much of it was tax and what the net price was. The reverse direction is the one people get wrong most often: the tax inside a total is not simply total × rate — that overstates it. The correct split is tax = total × rate/(1 + rate), which is exactly what this tool computes, so a 110 total at a 10% rate contains exactly 10.00 of tax on a 100.00 net price. Because rates are entered by you rather than bundled into a rates database, the tool stays correct for any combined rate — state, county, city and special district taxes added together — and it never goes stale when rates change. Enter any numbers and results update live as you type, with everything computed locally in your browser. Note the scope: this is pure percentage arithmetic for pricing and receipts; it does not file, remit or advise on tax rules.