How the Sales Tax calculator works
Add sales tax
Total = Price × (1 + rate)
Remove sales tax
Price before tax = Total ÷ (1 + rate)
Find the rate
Rate = (Total − Price) ÷ Price × 100
Worked example
A purchase of $100.00 taxed at a combined 8.25% has $8.25 of sales tax, so the total is $108.25.
Working backward from a receipt is just as easy: a $108.25 total at 8.25% means the price before tax was $100. Taking 8.25% off the total would give $99.32, which is wrong, because the tax was figured on the lower price.
How to calculate sales tax
Multiply the price by the rate written as a decimal: $45 at 7% is $45 × 0.07 = $3.15 of tax, for a total of $48.15. To find the price before tax from a total, divide by 1 plus the rate: $48.15 ÷ 1.07 = $45. To find the rate from a receipt, divide the tax by the price before tax: $3.15 ÷ $45 = 7%.
States without a statewide sales tax
Alaska, Delaware, Montana, New Hampshire and Oregon have no statewide sales tax, although many Alaska towns and some Montana resort areas charge a local one. Many states also exempt groceries or tax them at a lower rate, so the rate can depend on what you buy as well as where you buy it.
Combined sales tax rates
States set a base sales tax rate, and counties, cities and special districts can add their own, so the rate depends on the exact location of the sale. Two stores in the same metro area can charge different rates. Find your combined rate with your state’s lookup tool and enter it above.
For sellers
Sales tax you collect belongs to the state, not your business, so it doesn’t count as revenue. Keep it separate and file returns on the schedule your state assigns. Since 2018, states can also require online sellers to collect tax on sales delivered to their residents once sales pass a set amount.
Related calculators
To see a sale price after a discount and tax together, use the discount calculator. For a car purchase with sales tax and a trade-in, use the car loan calculator, and for property taxes on a home, the property tax calculator.
Assumptions and limits
- One combined rate applies to the whole purchase. Some items, such as groceries or clothing in certain states, are taxed at lower rates or not at all.
- Prices are rounded to cents as a receipt would be.
Frequently asked questions
How do I calculate sales tax?
Multiply the price by the tax rate as a decimal. At 8.25%, a $100 purchase has $8.25 of tax, for a total of $108.25.
How do I take sales tax out of a total?
Divide the total by one plus the rate. A $108.25 receipt at 8.25% tax means a price of $108.25 ÷ 1.0825 = $100 before tax. Subtracting 8.25% of the total would give the wrong answer.
What is my sales tax rate?
It is the state rate plus any county, city and special district rates where you buy, or where an item is delivered for online orders. Your state revenue department's website has a rate lookup by address.
Which states have no sales tax?
Alaska, Delaware, Montana, New Hampshire and Oregon have no statewide sales tax, although some Alaska towns charge a local one.
Can I deduct sales tax on my federal return?
If you itemize, you can deduct state and local sales taxes instead of state income taxes, within the overall cap on state and local tax deductions. The IRS has a calculator for the amount.
Sources and method
- Topic no. 503, Deductible taxes · Internal Revenue Service
- Sales Tax Deduction Calculator · Internal Revenue Service
Formulas and figures checked against these sources on November 11, 2026. The calculator runs entirely in your browser; nothing you type is sent to us or stored. Results are estimates for education, not financial, tax or legal advice, and MonyPulse is not a lender, tax preparer or investment adviser. Found an error? Tell us. See how we build and test our calculators and our editorial standards.