Sales Tax Calculator
Add sales tax to any amount and see the total instantly.
Your numbers
Total with tax
- Amount
- $100.00
- Sales tax
- $8.50
- Total
- $108.50
Sales tax is added at the point of sale and varies enormously depending on where you are. Because it's layered from state, county, and city rates, two towns a few miles apart can charge noticeably different amounts on the same purchase. Here's how it works and how to calculate it.
What is sales tax?
Sales tax is a percentage added to the price of goods (and some services) that the seller collects and passes to the government. In the US there's no national sales tax — each state sets its own, and local jurisdictions add their own on top.
How to calculate sales tax
The formula is simple:
Sales tax = price × (tax rate ÷ 100), and total = price + sales tax
On a $100 purchase at an 8.5% combined rate: 100 × 0.085 = $8.50 tax, for a $108.50 total. The Sales Tax Calculator does this instantly for any amount and rate.
Why rates vary so much
Your final rate is usually a combination:
- State rate — from 0% (a handful of states have none) to over 7%.
- County and city rates — added on top, sometimes several percent.
- Special districts — transit, stadiums, and other local levies.
Combined rates commonly land between 6% and 10%, but can be higher. Always use your exact local rate.
What's taxable?
It depends on the state. Many exempt groceries, prescription medicine, and some clothing, while taxing most other goods. Services are increasingly taxed but vary widely. If you're a business, knowing what's taxable in your state is essential for charging correctly.
Sales tax for online sellers
Since the 2018 Wayfair decision, online sellers can be required to collect sales tax in states where they have "economic nexus" (a threshold of sales or transactions) — even without a physical presence. If you sell online, you may need to collect and remit tax in multiple states; most platforms can automate this.
The bottom line
Sales tax is price × rate, but the rate is a stack of state and local pieces that varies by location. Use your exact combined rate in the Sales Tax Calculator to find the tax and total on any purchase, and if you sell online, check your nexus obligations state by state.
Frequently asked questions
How do I calculate sales tax?
Multiply the price by the tax rate as a decimal: price × (rate ÷ 100). On a $100 item at 8.5%, that’s $8.50 tax, for a $108.50 total. The calculator does this for any amount and rate.
Why is sales tax different in every city?
US sales tax is layered: a state rate plus county, city, and sometimes special-district rates. Those local additions are why two nearby towns can charge different combined rates on the same purchase.
Which states have no sales tax?
A handful of US states have no statewide sales tax — currently Alaska, Delaware, Montana, New Hampshire, and Oregon (though some local taxes can still apply in Alaska). Everywhere else charges a state rate plus local additions.
What is exempt from sales tax?
It varies by state, but many exempt groceries, prescription medicine, and sometimes clothing. Services are taxed inconsistently. Check your state’s rules to know exactly what is and isn’t taxable.
How do I find the sales tax from a total price?
To back out the tax from a tax-inclusive total, divide the total by (1 + rate ÷ 100) to get the pre-tax price, then subtract it from the total. For example, $108.50 ÷ 1.085 = $100 pre-tax, so $8.50 was tax.
Do online purchases have sales tax?
Usually yes. Since the 2018 Wayfair ruling, online retailers must collect sales tax in states where they exceed an economic-nexus threshold, so most online purchases are taxed at your local rate.
What is a typical combined sales tax rate?
Combined state-plus-local rates commonly fall between about 6% and 10%, though some areas are lower or higher. Always use your exact local rate rather than an average for an accurate total.
Do I charge sales tax as a small business?
If you sell taxable goods in a state where you have nexus (physical presence or enough sales), you generally must register, collect sales tax at the buyer’s rate, and remit it. Most sales platforms can automate the collection.