Sales Tax Calculator.
Type a price and the sales tax rate that applies where you sell, and this calculator returns the tax and the total, or works backwards from a total that already includes tax.
Look up the rate for a delivery address on your state revenue department site. Directory: Federation of Tax Administrators, state tax agencies. Multi-state sellers: Streamlined Sales Tax Governing Board.
This calculator does not store a table of rates, because US rates change by jurisdiction and by date. Enter the rate published by the state or local authority for the place where the sale is sourced. Nothing you enter is sent anywhere.
Sales Tax Calculator is a free online tool from Neweb (neweb.ai) for small businesses, with no sign-up. Type a price and the sales tax rate that applies where you sell, and this calculator returns the tax and the total, or works backwards from a total that already includes tax.
| Cost | Free, no account, no watermark |
|---|---|
| Built for | small businesses, freelancers and sole proprietors |
| Made by | Neweb, the AI website builder and online presence manager (free plan; paid plans from $9/month billed yearly) |
Facts checked October 2026.
What you'll get.
A real example of what this tool produces. Run it above with your own inputs.
Sales tax in the United States is a percentage added at the point of sale, set by each state and often topped up by counties, cities and special districts. Five states have no general sales tax, several have rates above 7 percent before local additions, and thousands of local jurisdictions change their rates throughout the year. That is why this calculator asks you for the rate rather than guessing it: you enter the state rate and any local rate for the place where the sale is sourced, and it does the arithmetic.
Use it forwards, to add tax to a price and show the customer a total, or backwards, to find the pre-tax price and the tax inside a receipt total for an expense report, a refund or your books. A quantity field handles multi-unit sales, and the results show the combined rate, the tax, the total and the tax per unit. It also works for Canadian provincial sales taxes if you enter the GST and PST rates in the two fields.
The calculator is free, runs in your browser and comes from Neweb, the AI website builder for small businesses (free plan, paid plans from $9/month billed yearly, $19 month-to-month). It links to the official state directories so you can find the correct rate rather than trusting a table that may be out of date.
How to use the sales tax calculator
Choose Add tax to a price if you know the pre-tax price, or Back out tax from a total if you have a receipt total that already includes tax.
Enter the price (or total) and the quantity if you are selling more than one unit.
Look up the state rate and any local rate for the delivery or store address on your state revenue department website, linked below the calculator, and type them in.
Click Calculate. The panel shows the combined rate, the price before tax, the sales tax and the total.
Show the tax as a separate line on the receipt or invoice; most states require tax to be stated separately from the price.
Why this matters for your business
Rates are hyper-local. Two shops a mile apart can charge different combined rates because one sits inside a transit district. Hard-coded rate tables go stale within months, which is why this tool asks you for the current published figure instead.
Online sellers now collect in states they never visit. Since the 2018 Wayfair decision, most states require out-of-state sellers to collect sales tax once they pass an economic nexus threshold, commonly around $100,000 in sales or 200 transactions, though the exact figures vary by state. Knowing how to compute tax at a destination rate is part of running an online store.
Under-collecting comes out of your pocket. If you charge too little tax, the state still expects the full amount from you. Getting the rate right at the point of sale is cheaper than fixing it at audit.
Tips for better results
- Enter the state and local components separately so you can see how much of the combined rate is local; local portions change far more often than state rates.
- Most states source sales to the delivery address (destination-based); a few source to the seller's location (origin-based). Check which rule your state uses before choosing which address to look up.
- Groceries, clothing, prescription drugs and digital goods are taxed differently from state to state; a 0 percent rate here is correct for exempt items in your state.
- For an expense report, use reverse mode on the receipt total to show the pre-tax amount and the tax separately.
- Keep a note of the rate and the date you looked it up with each invoice; it is your evidence if a rate changed mid-quarter.
- If you sell into many states, a tax engine or a marketplace that collects on your behalf will save hours; this calculator is for quick checks and single-location sellers.
Example
A real-world walkthrough
A bike shop in a Texas suburb sells a child seat for $249.99. The owner looks up the address on the Texas Comptroller rate locator and finds the state rate of 6.25 percent plus local taxes of 2 percent. She enters 249.99, 6.25 and 2 and sees a combined rate of 8.25 percent, tax of $20.62 and a total of $270.61 to charge at the till.
Later, an employee hands in a $54.00 receipt from a city with a 7 percent combined rate for a bookkeeping entry. Reverse mode shows $50.47 before tax and $3.53 of tax, which go into the ledger as separate lines.
Frequently asked questions
Why doesn't the calculator know my state's rate?
Because a single published rate would be wrong for most addresses. State rates are only part of the picture: counties, cities and special districts add their own percentages, and those local rates change frequently. A built-in table would be out of date quickly and could cause you to under- or over-collect. Instead, the tool links to the Federation of Tax Administrators directory of state revenue departments, where each state publishes a rate lookup by address, and you enter the figure you find.
How do I calculate sales tax from a total?
Divide the total by one plus the combined rate as a decimal, which gives the pre-tax price; the difference is the tax. For a $54.00 total at 7 percent, $54.00 ÷ 1.07 = $50.47, so the tax is $3.53. Taking 7 percent of $54.00 would give $3.78, which is wrong. Select "Back out tax from a total" and the calculator does this for you.
Do I charge the rate where I am or where the customer is?
It depends on the state. Most states are destination-based, meaning you charge the rate at the delivery address. A minority, including Texas for in-state sales in some situations, are origin-based and use the seller's location. For sales shipped from out of state, destination rules almost always apply. Check your state revenue department's sourcing rules and, if in doubt, ask a tax professional.
What is economic nexus and does it apply to a small online shop?
Economic nexus is the rule, allowed by the US Supreme Court in South Dakota v. Wayfair (2018), that a state can require an out-of-state seller to collect its sales tax once the seller passes a sales threshold there. Many states use $100,000 in annual sales or 200 transactions, but thresholds vary and some states have dropped the transaction count. A small shop that sells mostly in its home state usually only needs to collect at home, but it is worth checking any state where sales are growing.
Can I use this for Canadian GST, HST or PST?
Yes, as a calculator. Choose CAD, enter the federal GST (5 percent) in the state field and the provincial sales tax in the local field, or enter the full HST rate for a harmonized province in one field and leave the other blank. The tool then shows the combined rate, the tax and the total. Canadian rules on which items are taxable differ from the US, so confirm them with the Canada Revenue Agency or your province.
Is this tax advice?
No. The calculator multiplies the figures you give it. Whether an item is taxable, which address governs the rate, whether you have nexus in a state and when to file are legal questions that depend on your business and the states involved. Neweb offers this tool as a free convenience for small businesses; confirm anything that affects a return with the state revenue department or a tax professional.
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