🧾 Sales Tax Calculator
Calculate sales tax and the total price of a purchase, or work backward from a total to find the pre-tax price.
Purchase Details
Your Result
Enter the pre-tax price and tax rate to find the tax amount and total price.
How the Sales Tax Calculator Works
Sales tax is a percentage-based tax added to the price of goods and services at the point of sale. This calculator can compute the tax forward from a pre-tax price, or reverse it from a total (tax-included) amount to find the original price.
Formulas
Reverse: Price = Total / (1 + Rate / 100), Tax = Total − Price
Frequently Asked Questions
How do I calculate sales tax from a total price?
Divide the total price by (1 + tax rate as a decimal). This gives you the pre-tax price; subtract it from the total to get the tax amount.
Why can't I just subtract the tax rate percentage from the total?
Because the tax rate applies to the pre-tax price, not the total, simply subtracting the percentage from the total overstates the tax. You must divide by (1 + rate) instead.
Do sales tax rates vary by location?
Yes, sales tax rates vary widely by country, state, and even city or county. Check your local tax authority for the exact rate that applies to you.