Sales tax calculator
Add sales tax to a price, take it out of a total that includes it, or find the rate from a receipt.
- Formula and assumptions shown
- Table and CSV export
- Runs in your browser
How it works
Enter a price and the sales tax rate to see the tax and the total. The rate is yours to enter: US sales tax is set by states and often by counties and cities too, so the combined rate differs from place to place, and some items are exempt or taxed at a different rate.
Sales tax = price × rate ÷ 100. Total = price × (1 + rate ÷ 100). Price before tax = total ÷ (1 + rate ÷ 100). Tax included = total − price before tax. Rate = (total − price) ÷ price × 100.
To take tax out of a total that already includes it, divide by one plus the rate. A $129.60 total at 8% is $129.60 ÷ 1.08 = $120 before tax. Taking 8% off the total instead gives $119.23, because the tax was worked out on the smaller pre-tax price, not on the total. The third mode finds the rate from a receipt: the tax divided by the price before tax.
The same arithmetic applies to VAT and GST in other countries. Where prices are shown with VAT included, the remove-tax mode gives the price before VAT; at the UK standard rate of 20%, divide by 1.2.
Assumptions
- One combined rate applies to the whole amount; items taxed at different rates need separate calculations.
- The rate is entered by you; the calculator holds no state or local rate tables.
- Tax is shown rounded to the cent but kept exact; stores round the tax on each receipt.
- Use tax, excise taxes and fees such as bottle deposits are not included.
Worked example
Worked examples on this page use US dollars.
$120 purchase at an 8% combined rate
8% of $120 is $9.60, for a total of $129.60, so the tax is 7.41% of what you pay. Taking the tax out of $129.60 at 8% gives back $120.00; the shortcut $129.60 × 0.92 gives $119.23, which is $0.77 too low. A receipt showing $120 before tax and $129.60 in total means a rate of 8%.
Step by step
- Turn the rate into a decimal. 8% ÷ 100 = 0.08, so the multiplier for the total is 1 + 0.08 = 1.08.
- Work out the tax. $120 × 0.08 = $9.60 of sales tax.
- Add it to the price. $120 + $9.60 = $129.60, the same as $120 × 1.08. The tax is 7.41% of the total paid.
- Take the tax back out. $129.60 ÷ 1.08 = $120.00. Multiplying $129.60 by 0.92 instead gives $119.23, which is $0.77 too low.
How to read your result
In the add-tax mode the headline is the total with tax; in the remove-tax mode it is the price before tax; in the find-the-rate mode it is the tax rate. The tax itself and the other two amounts are always listed underneath.
The table repeats the calculation at whole rates from 4% to 10% plus your own rate, which helps when you are unsure of the local rate or are comparing places.
What changes the result most
- The combined rate
- On a $120 purchase, each percentage point of tax adds $1.20: $6.00 at 5%, $9.60 at 8% and $12.00 at 10%.
- Adding versus removing tax
- 8% of $120 is $9.60, but the tax inside a $129.60 total is also $9.60, which is only 7.41% of that total.
Questions
How do I calculate sales tax?
Multiply the price by the tax rate as a decimal. At 8%, $120 × 0.08 = $9.60 in tax, for a total of $129.60. Multiplying by 1.08 gives the total in one step.
How do I calculate reverse sales tax?
Divide the total by one plus the rate. A $129.60 total at 8% is $129.60 ÷ 1.08 = $120 before tax, so the tax was $9.60. Multiplying the total by 0.92 is a common mistake that gives $119.23.
What sales tax rate should I use?
The combined state and local rate where the sale takes place, from your state revenue department. Rates differ by state, county and city. Five states have no statewide sales tax (Alaska, Delaware, Montana, New Hampshire and Oregon), and of those only Alaska allows local sales taxes, according to the Tax Foundation's July 2026 report.
Can I use this as a VAT calculator?
Yes, the math is the same. Enter the VAT rate to add VAT to a net price, or use the remove-tax mode on a VAT-inclusive price. At the UK standard rate of 20%, £120 including VAT is £100 before VAT. EU standard rates must be at least 15%.
How do I find the sales tax rate from a receipt?
Divide the tax by the price before tax and multiply by 100. $9.60 of tax on $120 is $9.60 ÷ $120 × 100 = 8%.
More in Everyday & business
Sources
- Tax Foundation: state and local sales tax rates, midyear 2026 (July 6, 2026)
- GOV.UK: VAT rates on different goods and services
- European Commission: VAT rates
These references explain the concepts behind the calculation. They do not endorse this site. Estimates leave out any cost or condition you did not enter.