The formula
Sales tax is a percentage of the price. Turn the rate into a decimal by dividing by 100, then multiply:
- Tax = price × rate ÷ 100
- Total = price + tax, which is the same as price × (1 + rate ÷ 100)
Texas writes it the same way in its tax code: the total tax is computed by multiplying the combined applicable tax rates by the sales price. Combined is the key word. In most states the rate on your receipt is the state rate plus whatever local governments add, and the formula uses the sum.
Example at the Texas average combined rate of 8.2%: a $49.99 pair of headphones costs 49.99 × 0.082 = 4.0992 in tax, rounded to $4.10, for a total of $54.09. The sales tax calculator does this for any amount and any state, and the percentage calculator handles the bare "x percent of y" step if you want to check by hand.
Adding tax to a price in one step
Shopping with a budget, you want the total, not the tax. Multiply once by 1 plus the decimal rate. At 8.2% the multiplier is 1.082:
- $100.00 × 1.082 = $108.20
- $250.00 × 1.082 = $270.50
- $1,299.00 × 1.082 = $1,405.52
Sales are taxed on the price you pay, after the markdown. For a 30% off item, take the discount first with the discount calculator, then add tax to the sale price. Doing it the other way round, tax on the full price minus 30% of that, gives the same total only by accident of arithmetic: 100 × 1.082 × 0.7 and 100 × 0.7 × 1.082 are both 75.74, but the tax line on the receipt is 5.74, not 8.20.
Backing tax out of a total
A receipt shows $54.10 and you need the pre-tax price for an expense report. The trap is to take 8.2% of 54.10, which is $4.44. That is too much, because the 54.10 already includes the tax, so the percentage is applied to an inflated base.
Divide instead of multiplying:
- Price before tax = total ÷ (1 + rate ÷ 100) = 54.10 ÷ 1.082 = $50.00
- Tax = total − price before tax = 54.10 − 50.00 = $4.10
The sales tax calculator has a mode for this; enter the total and it splits it. The same division works for any inclusive price, which matters in the VAT section below.
Combined state and local rates, with real numbers
According to the Tax Foundation's midyear 2026 survey, 45 states levy a statewide sales tax and five do not: Alaska, Delaware, Montana, New Hampshire and Oregon. 38 states allow local sales taxes, and Alaska is one of them, so Alaskans pay local tax with no state tax on top. The Tax Foundation weights local rates by population to get an average for each state, and those averages are what the calculator and the table below use (state rates as of July 1, 2026, local rates as of January 1, 2026).
The highest average combined rates are Louisiana at 10.13%, Tennessee at 9.61%, Washington at 9.57%. The tax on three round amounts at five real averages:
| State (average combined rate) | Tax on $25.00 | Tax on $50.00 | Tax on $100.00 |
|---|---|---|---|
| Florida (6.98%) | $1.75 | $3.49 | $6.98 |
| Texas (8.2%) | $2.05 | $4.10 | $8.20 |
| New York (8.54%) | $2.14 | $4.27 | $8.54 |
| California (9.03%) | $2.26 | $4.52 | $9.03 |
| Louisiana (10.13%) | $2.53 | $5.07 | $10.13 |
Each state link opens a page with that state's base rate, local average, grocery rules and, for most states, the official address lookup, for example the Texas sales tax page. Two numbers in the data deserve a note. New Jersey's average combined rate, 6.6%, is below its 6.625% state rate because qualifying sales in Urban Enterprise Zones and Salem County are taxed at half the state rate. And the Alaska figure, 1.82%, is entirely local tax.
Rounding to the cent
Multiplying rarely lands on a whole cent, so every state needs a rounding rule. Texas puts it in section 323.201 of its tax code: if the product has a fraction of a cent below one half, the fraction is not collected; if the fraction is one half cent or more, it is collected as one cent. In plain terms, round to the nearest cent and send a half cent up.
Look at the California row above. $50.00 × 9.03% = 4.515 exactly, a half cent, so the tax is $4.52, not $4.51. On $25.00 it is 2.2575, which rounds to $2.26. The calculator rounds the same way. The cents only ever differ by one, but if you are checking a receipt, that one cent is the difference between "matches" and "does not match".
Sales tax vs VAT
Most countries outside the US charge a value-added tax instead. The European Commission describes VAT as charged as a percentage of the sales price at every stage of production and distribution, collected fractionally through partial payments, where each business deducts the VAT it paid on its own purchases, so the tax is borne ultimately by the final consumer. A US sales tax shows up once, as its own line on the receipt at the register.
For you at the till the practical difference is where the tax hides. A US shelf price is before tax and the register adds it. When a price already includes the VAT, the question is the reverse one: how much of this $119.00 is tax? Same division as above: 119 ÷ 1.19 = 100 before tax at a 19% rate, 19 of tax. The VAT calculator works in both directions with the current rates for each country, for instance on its Germany page.
Frequently asked questions
Is sales tax charged on the price before or after a discount?
On what you actually pay. If a $60 jacket is 25% off, the tax is figured on $45, not $60. The discount calculator gives the marked-down price, and the sales tax calculator takes it from there.
Why does my receipt show a rate that is not in the table?
The table shows population-weighted state averages. The rate you pay is the state rate plus the exact local rates at the store's address, which can be a county and a city on top of each other. Most state pages link the official lookup tool for the address-level rate.
How do I find the pre-tax price from a receipt total?
Divide the total by 1 plus the rate as a decimal. A $54.10 total in a place with 8.2% tax is 54.10 ÷ 1.082 = $50.00 before tax, and the tax was the remaining $4.10. Multiplying the total by the rate instead gives $4.44, which is wrong, because the total already contains the tax.
Why is the combined rate higher than the rate on my state's website?
The state site shows the state rate. According to the Tax Foundation, 38 states let local governments add their own sales tax on top, and the combined rate is the sum. Texas charges 6.25% at the state level, but its local taxes average 1.95%, so the average combined rate is 8.2%.
Which states have no sales tax?
Delaware, Montana, New Hampshire, Oregon have no general sales tax at the state or local level. Alaska has no state sales tax either, but its cities and boroughs charge their own, 1.82% on average.