About the Sales Tax Calculator
A sales tax calculator adds tax to a pre-tax price and shows the total. US sales tax is added at the register rather than included in the shelf price, which is why the amount you pay differs from the advertised figure.
The formula
Total = price · (1 + rate / 100)The rate combines state, county, city, and sometimes special district taxes. Combined rates range from zero in a few states to over 10 percent in parts of Louisiana and Tennessee.
How to use this calculator
- 1Enter your Price Before Tax ($). The field starts at
100, which you can overwrite. - 2Enter your Sales Tax Rate (%). The field starts at
7.5, which you can overwrite. - 3Read the result straight away — it recalculates as you type, so there is no button to press. Use Share to copy a link that reopens the page with your exact numbers filled in.
Worked example
| Input | Value |
|---|---|
| Price Before Tax ($) | 100 |
| Sales Tax Rate (%) | 7.5 |
Result
Tax Amount: $7.50
Total Price: $107.50
Those are the values the page loads with, so you can reproduce this result yourself and then change one field at a time to see what drives the outcome.
Understanding your result
Rates are set at multiple levels and stack, which is why the applicable rate depends on the exact address rather than just the state. Two shops a mile apart can charge different rates if they fall in different county or district boundaries.
What is taxable also varies substantially. Many states exempt groceries, prescription medicines, and clothing below a threshold, while others tax everything at the same rate. Since the 2018 Wayfair decision, online retailers must collect sales tax based on the buyer's location once they exceed economic nexus thresholds in that state.
Things worth knowing
- To find the pre-tax price from a total, divide rather than subtract: a 107.50 total at 7.5 percent means 107.50 ÷ 1.075 = 100.
- Five US states have no statewide sales tax: Alaska, Delaware, Montana, New Hampshire, and Oregon.
- Groceries and prescriptions are exempt or reduced-rate in many states.
- Sales tax holidays suspend tax on specific categories for a few days, commonly before the school year.
- Businesses purchasing for resale can use a resale certificate to avoid paying tax at wholesale.
Frequently asked questions
How do I calculate sales tax?+
Multiply the price by the rate as a decimal, then add it to the price. At 7.5 percent, a 100 dollar item incurs 7.50 in tax for a total of 107.50.
How do I find the price before tax?+
Divide the total by 1 plus the rate. A 107.50 total at 7.5 percent gives 107.50 ÷ 1.075 = 100. Subtracting 7.5 percent from the total gives the wrong answer.
Why do rates differ within the same state?+
Because counties, cities, and special districts add their own rates on top of the state rate. The applicable combined rate depends on the specific address of the sale.
Do I pay sales tax on online purchases?+
Generally yes since the 2018 Wayfair ruling, which allows states to require collection from remote sellers exceeding economic nexus thresholds. The rate is based on your delivery address.