How to calculate sales tax
Sales tax is a percentage added to the price of goods and services at the point of sale. To find it, convert the rate to a decimal and multiply by the price:
Sales tax = Price × (Rate ÷ 100)
Total = Price + Sales tax
For a $50 purchase at an 8% rate: 50 × 0.08 = $4 in tax, so you pay $54 in total.
Working backward from a total
Sometimes you know the final, tax-included price and want the pre-tax amount — useful for receipts, reimbursements, or bookkeeping. Divide the total by 1 plus the rate as a decimal:
Price = Total ÷ (1 + Rate ÷ 100)
A $54 total at 8% works out to 54 ÷ 1.08 = $50 before tax, with $4 of tax. Switch this calculator to "Remove tax from a total" to do it automatically.
Why rates differ so much
In the United States there is no national sales tax. States set their own rates, and many let counties and cities add their own on top, so two stores a few miles apart can charge different totals. A handful of states levy no sales tax at all. Always use the combined rate for the exact location of the sale.
Frequently asked questions
How do you calculate sales tax on a price?
Multiply the price by the tax rate as a decimal. For a $50 item at 8% tax, that is 50 × 0.08 = $4 in tax, for a total of $54. Convert the percentage to a decimal by dividing by 100 before multiplying.
How do I find the pre-tax price from a total?
Divide the tax-included total by 1 plus the tax rate as a decimal. If you paid $54 at an 8% rate, the pre-tax price is 54 ÷ 1.08 = $50, and the tax was $4. This reverse calculation is handy for receipts and expense reports.
What is the difference between sales tax and a tax rate?
The tax rate is the percentage charged (for example, 8%). The sales tax is the dollar amount that rate produces on a specific purchase. The same 8% rate yields different sales-tax dollars depending on the price.
Do sales tax rates vary by location?
Yes. In the U.S., sales tax is set by states and often combined with county and city taxes, so the total rate varies widely by location — and some states have no sales tax at all. Enter the combined rate that applies to your purchase.
Disclaimer: Results are estimates for general informational purposes only. Actual sales tax depends on your jurisdiction and the type of item; some goods are taxed differently or exempt.