Free US Sales Tax Calculator

There is no federal sales tax in the United States. Instead, sales tax is set by states, and often stacked with county, city and special district rates on top, which is why the same product can cost a different amount in tax two towns apart. This calculator applies a combined rate you enter to a price so you can see the tax due and the total instantly.

Results

Combined rate8.000%
Pre-tax amount$100.00
Sales tax$8.00
Total charged$108.00
  • Pre-tax amount92.6%
  • Sales tax7.4%

Disclaimer: This calculator provides estimates only and does not constitute tax advice. Rates and thresholds change; confirm the current figures with your tax authority or accountant.

What the US Sales Tax Calculator does

US sales tax is a consumption tax charged on the sale of most goods and some services, collected by the seller at the point of sale and remitted to the relevant state and local tax authorities. It is destination-based in most states, meaning the rate that applies is generally the rate where the buyer takes delivery, not where the seller is located.

Methodology and formula

Sales tax due = Price x (Combined tax rate / 100); Total price = Price x (1 + Combined tax rate / 100), where Combined tax rate = State rate + County rate + City rate + Special district rate.

Worked example

Inputs
Price 250; state rate 6.25%; county rate 1%; city rate 1%; no special district.
Result
Combined rate 8.25%; sales tax due 20.63; total price 270.63.

The same $250 item sold across the state line where the combined rate is only 6% would carry $15 in tax instead of $20.63, a difference that comes entirely from local add-on rates rather than the state rate itself.

When to use this tool

Use this calculator to check the tax due on a specific sale once you know the applicable combined rate. Use the Invoice Generator to put that tax line on a customer-facing document, and the Product Pricing Calculator when you need to build a sell price before tax is even added.

About the US Sales Tax Calculator

Why sales tax rates differ by address, not just by state

Five states (Alaska, Delaware, Montana, New Hampshire and Oregon) charge no statewide sales tax, though Alaska allows local sales taxes. Everywhere else, the state rate is only the starting point: counties, cities and special taxing districts (transit, stadium, tourism) can each add their own percentage. Two addresses a few blocks apart, one inside a city limit and one outside it, can carry meaningfully different combined rates, which is why destination-based calculation matters for any business shipping across state lines.

Origin-based vs destination-based sourcing

Most states use destination-based sourcing: the rate charged is based on where the buyer receives the goods. A handful of states, including Texas and Arizona, use origin-based sourcing for in-state sales, where the seller's location sets the rate. Remote sellers crossing state lines almost always apply destination-based rules under the rules set by the buyer's state following the Supreme Court's Wayfair decision.

Economic nexus and when you must start collecting

Since South Dakota v. Wayfair (2018), states can require an out-of-state seller to collect sales tax once it crosses a sales or transaction threshold in that state, commonly $100,000 in sales or 200 transactions a year, though thresholds vary by state. Track your sales by state; crossing a threshold typically creates an obligation to register, collect and file even without a physical presence there.

What is usually exempt

Common exemptions include most unprepared groceries, prescription medication, and resale purchases covered by a valid resale certificate, though exact rules vary significantly by state. Services are taxed inconsistently: some states tax very few services, others tax a broad range including digital products and software as a service. Always confirm the taxability of your specific product or service with the destination state before pricing it.

Frequently asked questions

Is there a federal sales tax rate I should start from?

No. The United States has no federal sales tax. Every rate you apply is a combination of state, county, city and sometimes special district rates set independently by each jurisdiction, so you must look up the combined rate for the specific delivery address.

Which state's rate applies to an online sale shipped out of state?

In most states, the destination state's combined rate applies, based on where the buyer receives the goods, once you have economic nexus there. A minority of states use origin-based sourcing for their own in-state sales, so check the specific state's rules if you are unsure.

Do I charge sales tax on shipping charges?

It depends on the state. Some states tax the shipping charge whenever the underlying item is taxable, others exempt separately stated shipping charges. There is no single national rule, so confirm the treatment in the destination state before invoicing.

What is economic nexus and does it apply to me?

Economic nexus is a sales or transaction threshold that, once crossed, obligates a remote seller to register and collect sales tax in that state even without a physical presence there. Thresholds commonly sit around $100,000 in annual sales, but vary by state, so track sales by destination state.

Can I back out the pre-tax price from a tax-inclusive total?

Yes. Divide the tax-inclusive total by (1 + combined rate as a decimal) to find the pre-tax price, then subtract that from the total to find the tax amount. This is useful when a receipt only shows the final price paid.

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