Sales Tax Calculator
Estimate sales tax and your final purchase total using a state rate, local rate, and optional discount. Works for any state.
Enter Purchase Details
How Sales Tax Works — and Why the Rate Varies by Location
Sales tax is one of the most misunderstood taxes in the U.S. — because it's not one tax, it's dozens of overlapping taxes from different government levels. Here's what your estimate means and how to use it practically.
Why Sales Tax Is More Complicated Than It Looks
There's no federal sales tax in the United States. Instead, 45 states (plus D.C.) impose a state-level sales tax, and thousands of counties, cities, and special districts stack additional local taxes on top. The combined rate for the same item can vary from 0% to over 10% depending on exactly where you buy it — sometimes changing from one zip code to the next. This calculator uses combined state + average local rates by state.
How to Interpret Your Sales Tax Estimate — Step by Step
- Understand what "combined rate" means. The rate this calculator uses is the state sales tax rate plus the average local tax rate for that state. Your actual rate may differ slightly depending on your specific city or county — especially in states like Colorado, Louisiana, or Alabama where local rates vary widely.
- Know what's taxable (and what isn't). Most states exempt groceries, prescription drugs, and some services from sales tax. The taxable amount you enter should only include taxable items — don't include food (in most states), medicine, or other commonly exempt categories.
- Pre-tax vs. total price. This calculator works forward from the pre-tax price. If you already know the total price paid and want to back out the tax, divide the total by (1 + tax rate) to get the pre-tax price, then subtract.
- Business purchases vs. personal purchases. If you're a reseller or business purchasing items for resale, you may qualify for a sales tax exemption using a resale certificate. This calculator is designed for consumer purchases.
3 Common Mistakes When Using This Calculator
What to Do Next
- Moving to or purchasing in a new state? Use our state income tax hub to compare the full tax picture — income tax, sales tax, and property tax — across states.
- Self-employed or running a business? Sales tax obligations for businesses are separate from this calculator — contact your state's Department of Revenue for business sales tax registration.
- Buying a home? Real estate is generally exempt from sales tax, but transfer taxes may apply — see our home purchase tax guide for what to expect.
How Sales Tax Is Calculated
Sales tax is calculated on the taxable purchase amount after any discount, using the combined state and local rate you enter.
Find the Taxable Amount
Start with the full purchase price and subtract any discount. The remaining amount is what sales tax is applied to.
Add State and Local Rates
The combined tax rate is your state rate plus any city, county, or district tax rate. Rates vary widely by location.
Calculate the Tax Amount
Multiply the taxable amount by the combined rate (as a decimal) to get the estimated sales tax dollar amount.
Calculate the Final Total
Add the estimated sales tax to the taxable amount to get the final out-of-pocket cost.
// Step 1 - Taxable Amount
Taxable Amount = Purchase Amount - Discount Amount
// Step 2 - Combined Rate
Combined Rate = State Rate + Local Rate
// Step 3 - Sales Tax
Sales Tax = Taxable Amount x (Combined Rate / 100)
// Step 4 - Final Total
Final Total = Taxable Amount + Sales Tax
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Frequently Asked Questions
Disclaimer: This calculator provides estimates for educational purposes only. Actual sales tax may vary based on exact location, item type, applicable exemptions, and current local rules. It is not tax, legal, or financial advice. Consult a qualified tax professional for specific guidance.