§ 01 / TOOL
$50 at 7% sales tax.
STATUS ACTIVEMODE ADD TAXLATENCY <1MS
> INPUT
MODE ADD TAX
$
PLUS TAX
PLUS TAX
%
TOTAL.
WITH TAX
// RESULT
$53.50
// TAX
$3.50
// FORMULA
$50.00 + 7% = $53.50
$50.00 with 7% sales tax is $53.50 — tax is $3.50.
§ 02 / ABOUT
How sales tax adds up.
Sales tax is a percentage of the pre-tax price, added at checkout. The math is simple: tax = price × rate, then total = price + tax. The tricky part is figuring out which rate actually applies.
// WHY RATES VARY
- State tax — 0% in Oregon, Montana, New Hampshire, Delaware, Alaska; up to about 7.25% in California.
- County + city tax — stacked on top of the state rate. A "9.5% sales tax" in a US city usually means 6% state + 3.5% local.
- District and special taxes — transit, tourism, stadium — add more layers in some zip codes.
- Category exemptions — groceries, prescription drugs, and clothing are exempt or taxed lower in many states.
// WORKING BACKWARDS
To find the pre-tax price from a total, divide by (1 + rate), not subtract the rate. $108 total at 8% tax isn't $108 − 8% = $99.36; it's $108 / 1.08 = $100.
Related: Discount, Tip, Percentage.
§ 02 / FAQ
Questions. Answered.
How is sales tax calculated?+
Multiply the pre-tax price by the tax rate (as a decimal). So $100 × 0.0825 = $8.25 tax, total $108.25. Type the price on the left and the rate on the right — tax and total appear instantly.
What sales tax rate should I use?+
It depends on where the purchase is made. US state sales tax ranges from 0% (Delaware, Montana, New Hampshire, Oregon) to ~7.25% (California). Local/city/county taxes often add 1–5% on top. Look up your jurisdiction or check the receipt from a similar recent purchase for the effective combined rate.
Are decimals allowed in the rate?+
Yes. Many jurisdictions use quarter or eighth-percent rates (e.g., 8.25%, 7.375%). Type it as-is.
Does this work internationally (VAT, GST)?+
Yes, for the arithmetic. VAT and GST are computed the same way: pre-tax price × rate = tax, added to total. Rates differ: UK VAT 20%, Australia GST 10%, Canada HST 13–15%, EU VAT 17–27%. Just enter your local rate.
Can I reverse-calculate the pre-tax price?+
Not in this tool yet. If the total is $108.25 and the rate is 8.25%, divide total by (1 + rate/100): 108.25 ÷ 1.0825 = $100. We may add a reverse mode if people ask — let us know.
Does the URL update so I can share?+
Yes. As you type, the URL updates to /sales-tax/100-8.25 (price-rate). Copy the URL bar or use the SHARE button to send the exact calc to someone.
§ 04 / TOOLS
Related calculators.
§ 05 / READING