Sales Tax Calculator
Free sales tax calculator to find the tax amount and total price at any rate, or work backward from a total to the pre-tax price. Includes state sales tax rates, no signup.
Rate Breakdown
How This Is Calculated
Add tax: tax = price x combined rate, total = price + tax. Reverse: pre-tax = total / (1 + rate), tax = total - pre-tax.
Everything behind the Sales Tax Calculator
Formulas, reference charts, and detailed answers — expand any section you need.
Sales Tax Rates by State
| State | Base Rate |
|---|---|
| California | 7.25% (highest base) |
| Tennessee, Louisiana | ~9.5% combined average (highest with local) |
| Colorado | 2.9% (lowest base with tax) |
| Alaska, Delaware, Montana, New Hampshire, Oregon | 0% (no state sales tax) |
Rates change; the calculator's state table is labeled with its update year.
Sales Tax Calculator: Find the Tax and Total Price
This sales tax calculator works in both directions. Enter a price and your rate, and it shows the sales tax amount and total instantly. Enter a total from a receipt, and the sales tax calculator extracts the pre-tax price and the tax hidden inside it. Select your state to autofill the base rate, add your local rate if one applies, and the combined rate handles the rest.
Example: A $250 purchase at a combined 8.25% rate carries $20.63 in sales tax, for a total of $270.63.
How to Calculate Sales Tax
To calculate sales tax, multiply the price by the tax rate as a decimal: $80 at 7% is $80 x 0.07 = $5.60 tax, $85.60 total. The mental shortcut: 1% of the price is the price with the decimal moved two places left, then scale up. The sales tax calculator applies the exact math instantly, including combined state and local rates.
Reverse Sales Tax Calculator: Price Before Tax
A reverse sales tax calculator answers the question receipts create: what was the price before tax? Divide the total by 1 plus the rate: a $108.25 total at 8.25% means $108.25 / 1.0825 = $100 pre-tax, with $8.25 as tax. Business owners use this constantly to extract tax from tax-inclusive totals for bookkeeping, and it is the direction basic calculators get wrong by subtracting the percentage instead of dividing.
Sales Tax Calculator for Small Business Pricing
Business owners use a sales tax calculator in both directions: forward to quote a customer the out-the-door price, and reverse to extract the tax portion from tax-inclusive sales for filing. The separate state and local rate display matches how sales tax returns are actually reported, and the reverse mode turns a day of receipt math into seconds per entry.