Sales Tax Calculator

Enter the price before tax and the rate. The calculator works out:

• Tax amount: amount × rate ÷ 100
• Total with tax: amount + tax

With the defaults, $100 at 8.25% is $8.25 of tax and a $108.25 total. The third line repeats the pre-tax amount so you can copy all three figures onto a quote or invoice.

The calculator only adds tax. If you have a receipt total that already includes tax and want the price before it, you need to divide rather than multiply, which is what the reverse sales tax calculator does. Results drop a trailing zero, so $6.60 shows as $6.6.

There is no federal sales tax in the US. Rates are set by states and by local governments, and a single sale can carry a state rate plus county, city or district rates on top. Add them together and enter the combined figure. A sale taxed at 6% by the state, 1.5% by the county and 0.75% by the city uses 8.25%.

As of January 2026, five states have no statewide sales tax: Alaska, Delaware, Montana, New Hampshire and Oregon. Alaska lets local governments levy their own, so a 0% rate isn't guaranteed there.

Here is what the same $250 purchase costs at a range of combined rates:

Which local rates apply depends on where your state treats the sale as taking place, so check its tax department for the rules and current local rates before you set up a rate.

Tax is rounded to the cent, and where you round changes the answer. Take three items at 8.25%:

Enter the $17.27 subtotal in the calculator instead and the tax comes to $1.42. Neither is a mistake; they are two rounding methods. Pick the one your invoicing or point-of-sale system uses and apply it consistently, so your records match what you actually charged.

When a store discount comes off the price before tax, the tax shrinks too. A $100 item with a $20 coupon, taxed on $80 at 8.25%, has $6.60 of tax and an $86.60 total, against $108.25 at full price. Whether a particular discount, coupon or shipping charge is part of the taxable amount depends on the state, so enter whatever your state counts as the taxable price.

To find the most you can spend before tax on a fixed budget, divide the budget by one plus the rate. With $500 all in at 8.25%, the limit is $461.89. Enter $461.89 here and the total comes back as exactly $500.