Sales tax calculator
Enter an amount and the sales tax rate to see the tax and the total. Switch the list to take the tax out of a total and find the price before tax.
This answer is for the example values in the boxes above. $100 plus 8.25% sales tax. Change the boxes to see your own answer.
The rate is yours to enter: use the combined rate for the address where you buy.
How it works
To add tax, the calculator multiplies the price by the rate and rounds the tax to the cent. The total is the price plus that tax.
To take tax out, it divides the total by one plus the rate. That gives the price before tax, and the tax is what is left of the total.
A worked example
A purchase costs $100 and the combined rate is 8.25 percent. The tax is $8.25 and the total is $108.25.
For the other direction, take a receipt total of $21.39 with 7 percent tax in it. The price before tax is $19.99 and the tax is $1.40. Add $1.40 to $19.99 and you are back at $21.39.
Which rate to enter
The rate is yours to enter, and it is the combined rate of the state and the local governments where you buy. The Tax Foundation counts 45 states with a state-level sales tax, and 38 states allow local taxes on top of it.
California has the highest state rate, 7.25 percent, and Colorado has the lowest rate above zero, 2.9 percent. The five states with no statewide tax are Alaska, Delaware, Montana, New Hampshire and Oregon. As of January 1, 2026, the average combined rate across the country, weighted by population, was 7.53 percent.
What it leaves out
Some goods are taxed at a lower rate or not at all, and the rule differs by state. Groceries are a common example, and the Tax Foundation notes that many governments exempt them. The calculator taxes the whole amount at one rate, so work out the taxed part of a mixed purchase first.
Sources
Questions
How do I calculate sales tax?
Multiply the price by the rate as a decimal and round to the cent. At 8.25% the tax on $100 is $8.25, and the total is $108.25.
How do I take sales tax out of a total?
Divide the total by 1 plus the rate as a decimal. A total of $21.39 with 7% tax in it is $21.39 divided by 1.07, which gives a price of $19.99 and tax of $1.40.
Which states have no sales tax?
Five states have no statewide sales tax: Alaska, Delaware, Montana, New Hampshire and Oregon. Of these, only Alaska lets its local governments charge one, according to the Tax Foundation.
What is the average sales tax rate in the United States?
The Tax Foundation puts the average of combined state and local rates, weighted by population, at 7.53% as of January 1, 2026. Louisiana has the highest average combined rate, at 10.11%.
Why does the rate change from town to town?
In 38 states local governments can add a sales tax of their own to the state rate. Use the combined rate that applies where you buy.
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