Home › Free Tools › Free Sales Tax Calculator
Add sales tax to a price, or work backwards from a tax-included total — instantly, with any rate.
Sales tax trips up a lot of small business owners because it works in two directions. Sometimes you have a pre-tax price and need to add tax to it. Other times you have a total that already includes tax and need to figure out how much of it was tax — for example when you’re reconciling a cash sale or filling out a return. This free calculator does both.
To add tax, enter the net (pre-tax) amount and your tax rate, and it shows the tax and the final gross price. To reverse it, switch to “Extract tax from total,” enter the gross amount and the rate, and it splits the total back into net and tax. The math updates the moment you type, so there’s nothing to submit and no signup.
The formulas are simple: to add tax, gross = net × (1 + rate ÷ 100). To extract tax from a tax-inclusive total, net = gross ÷ (1 + rate ÷ 100), and tax = gross − net. Knowing the reverse calculation is handy any time a receipt shows only the total.
If you invoice customers, StandupCRM applies the right tax automatically on every sale and keeps a running record for filing — but for a quick one-off check, this tool has you covered.
Multiply the price by the tax rate (as a decimal) and add it to the price. This tool does it automatically — enter the amount and rate.
Divide the total by (1 + rate/100) to get the net, then subtract to get the tax. Use the “Extract tax from total” mode.
Yes, completely free with no signup.
No. The calculation runs in your browser and nothing is sent anywhere.
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