Sales Tax Calculator
Calculate the sales tax owed on a purchase given the pre-tax price and the applicable tax rate — useful for budgeting US purchases (where sales tax is added at the register and varies state-by-state) and for working out the tax portion of any receipt where it is shown separately. Enter the price before tax and the combined state+local tax rate as a percentage, and the calculator returns the dollar amount of tax. To get the total amount payable, add this tax to the original price. This calculator does not handle the reverse direction (gross-to-net) or true European-style VAT, which is usually quoted inclusive of tax rather than added on top.
About this calculator
The formula is: sales tax = price × (rate ÷ 100). A $200 purchase at a 7.5% combined rate produces 200 × 0.075 = $15 in tax, for a total at the register of $215. Sales tax in the United States is generally a single-stage consumption tax collected by the retailer at the point of sale and remitted to state and local governments — the buyer pays it, the seller collects it. The combined rate you enter here should include all applicable layers: state rate (ranging from 0% in five states — Alaska, Delaware, Montana, New Hampshire, Oregon — to 7.25% in California), county rate, city rate, and any special district rates (transit, tourism, stadium). Combined rates in the US currently run from 0% (most of NH, DE, MT, OR) up to about 10% in parts of Louisiana, Tennessee, Arkansas, and Washington. Many states also exempt specific categories of goods entirely: most exempt unprepared groceries, prescription drugs, and clothing under a threshold; some exempt menstrual products, services, or digital goods. Sales tax is fundamentally different from value-added tax (VAT) used across Europe and most of the world: VAT is collected at every stage of production (with credits for the tax already paid), while US sales tax is collected only at the final retail sale. The final tax burden is similar — the difference is in how it is collected and who is liable for under-collection. Edge cases: the calculator returns 0 if either price or rate is 0; negative values produce negative tax (mathematically valid for refunds but unusual in a retail context); rates above 100% are accepted but never occur in real jurisdictions.
How to use
Example 1 — Buying a TV in California. You are buying a $799 television in Los Angeles, where the combined state + city sales tax rate is 9.5%. Enter 799 as Price Before Tax and 9.5 as Sales Tax Rate. Result: $75.91. Verify: 799 × 0.095 = 75.905, which rounds to $75.91. Your total at the register will be 799 + 75.91 = $874.91. ✓ A different California city with a 7.25% rate would have charged 799 × 0.0725 = $57.93, a $17.98 difference on the same TV simply due to local tax variation. Example 2 — Estimating monthly food bill tax. You spend $400/month at restaurants in Chicago, where prepared food is taxed at a combined rate of about 10.75% (including the city's restaurant tax). Enter 400 and 10.75. Result: $43. Verify: 400 × 0.1075 = 43.00. ✓ Over a year that is about $516 in sales tax just on restaurant meals — a useful figure to factor into a relocation comparison if you are considering moving to or from a high-sales-tax jurisdiction.
Frequently asked questions
What is the difference between sales tax and VAT?
Sales tax (used in the US) is a single-stage consumption tax collected only at the final retail sale to the end consumer — businesses generally do not pay sales tax on inventory they intend to resell. VAT (used across most of the rest of the world, including the EU, UK, Canada's GST/HST, Australia's GST, and most of Asia and Latin America) is a multi-stage tax collected at every step of production and distribution, but each business gets to deduct the VAT it paid on its own inputs — so the net effect at each stage is a tax only on the value added. The final consumer ends up paying roughly the same total tax in either system; the differences are in administrative burden, compliance enforcement (VAT has built-in cross-checking that makes it harder to evade), and pricing convention. VAT is typically quoted inclusive in displayed prices (the price tag is what you pay), while US sales tax is almost always quoted exclusive and added at the register.
How do I calculate the pre-tax price from a total that includes tax?
Use the reverse formula: pre-tax price = total ÷ (1 + rate ÷ 100). If your receipt shows $107.50 total and the local rate is 7.5%, the pre-tax price was 107.50 ÷ 1.075 = $100, and the tax portion was $7.50. This is the formula to use for European VAT, where displayed prices are typically inclusive — at 20% VAT, the pre-tax (net) portion is total ÷ 1.20, and the VAT portion is total − net. A common mistake is to multiply the total by the rate directly (107.50 × 0.075 = $8.06), which gives a wrong answer because it computes tax on the total (which already includes tax) rather than on the pre-tax base. This calculator handles the forward direction only — for reverse calculations you need a dedicated gross-to-net or VAT-inclusive calculator.
Why do sales tax rates vary so much from one place to another?
In the US, sales tax is set independently by each state, county, and city — there is no federal sales tax. Five states have no statewide sales tax at all (Alaska, Delaware, Montana, New Hampshire, Oregon), though Alaska and Montana permit local taxes. California has the highest statewide rate at 7.25%, but Tennessee, Louisiana, Arkansas, Washington, and Alabama have the highest combined averages once local layers stack on top — pushing past 9% in many places and over 10% in some cities. Within a single state, rates can vary by neighbourhood: in Colorado, for example, the same product can carry six different combined rates depending on which city, county, and special district overlap at the address. This is why online retailers maintain enormous tax tables and why the Supreme Court's 2018 Wayfair decision (requiring out-of-state sellers to collect tax based on the buyer's location) created so much compliance work for small businesses.
What are the most common mistakes people make with sales tax?
The first is using a state-only rate when the combined state+local rate is what the buyer actually pays — the difference can easily be 2–3 percentage points, which on a major purchase adds hundreds of dollars. The second is forgetting that many states exempt specific categories: groceries (unprepared), prescription medicines, agricultural inputs, and sometimes clothing or back-to-school items during temporary tax holidays. The third is computing tax on the original price rather than the discounted price during a sale — sales tax always applies to the price actually paid, so a 30% discount reduces both the principal and the tax. The fourth is confusing sales tax with VAT for inclusive-price calculations; using the forward formula on a gross price overcharges yourself. Finally, businesses sometimes forget that buying inventory for resale is generally exempt with a resale certificate — and paying sales tax on resale inventory is one of the most common tax errors for new retailers.
When should I not use this calculator?
Do not use this calculator for European VAT, Canadian GST/HST, Australian GST, or any other jurisdiction where displayed prices are tax-inclusive — those require a reverse calculation (total ÷ (1 + rate/100)) to extract the tax portion, which this tool does not perform. Skip it for goods that may be exempt or taxed at a special reduced rate (groceries, prescription drugs, clothing under a state's threshold) — the rate field assumes a single flat rate applies to the entire purchase. It is the wrong tool for income tax, property tax, capital gains, or any tax other than transactional sales tax. Do not use it to calculate excise taxes (gas, alcohol, tobacco) which are typically per-unit specific taxes rather than ad valorem percentages. Finally, for business compliance use cases (filing returns, multi-jurisdiction sales, marketplace facilitator obligations), you need a real sales-tax compliance platform, not a quick calculator.