Use this free sales tax calculator to find the tax on any purchase and your total price. Enter the pre-tax amount and your local combined sales tax rate to see the tax and total instantly — no sign-up required.
How Sales Tax Is Calculated
Your total is simply the purchase amount plus the tax. The United States has no national sales tax; instead, the rate you pay is the combined total of state, county, city, and special-district taxes for the location where the sale takes place. Combined rates range from 0% in states like Oregon, Montana, New Hampshire and Delaware to over 10% in parts of Louisiana, Tennessee and Alabama.
Worked Example
On a $100 purchase at a 7.5% combined rate: tax = 100 × 0.075 = $7.50, for a total of $107.50.
Getting the Rate Right
- Destination-based: most states charge tax based on where the buyer takes delivery, not where the seller sits.
- Groceries and medicine are often taxed at a reduced rate or fully exempt.
- Online orders are generally taxed at your shipping address’s combined rate.
To work backward from a tax-included total to the pre-tax price, divide the total by (1 + rate ÷ 100).