🧾 Sales Tax Calculator
Enter a rate that fits where you are — sales tax and VAT both work the same way: amount × rate, added on top. Enter your values below — results update instantly, entirely on your device.
100 × 8%
if the amount was pre-tax
if 100 already includes 8% tax
How the sales tax calculator works
Tax = amount × rate ÷ 100; total = amount + tax. To reverse a tax-inclusive price to its pre-tax value: pre-tax = total ÷ (1 + rate ÷ 100). Enter whatever rate applies to you — the calculator is rate-agnostic, so it works for any state, country or VAT band.
Example: 100 at 8% → 8 tax, 108 total. Reversed: 108 including 8% tax comes from a 100 pre-tax price.
Because you type the rate, this works for U.S. state and local sales tax, UK/EU VAT (20%, 5%, etc.), GST and any other percentage tax. The reverse figure is the useful one for receipts and invoices — it recovers the net price from a gross, tax-inclusive total. We deliberately don't hard-code rates, since they change and vary by location; use your current local rate.
Frequently asked questions
How do I add sales tax to a price?
Multiply the price by the tax rate as a decimal, then add it: $100 at 8% is 100 × 0.08 = $8 tax, for a $108 total. This calculator shows the tax and total instantly for any rate you enter.
How do I find the pre-tax price from a total?
Divide the tax-inclusive total by (1 + rate). A $108 total that includes 8% tax came from 108 ÷ 1.08 = $100 pre-tax. The calculator shows this reverse figure automatically — handy for invoices and expense reports.
Does this work for VAT and GST too?
Yes — VAT, GST and sales tax are all percentage taxes that work the same arithmetic way. Just enter the applicable rate (20% UK standard VAT, 5% reduced, etc.). The tool doesn't assume any jurisdiction.
Why don't you fill in my local tax rate automatically?
Because rates change and vary widely by state, city and country — a hard-coded rate would quickly be wrong for someone. Entering your own current rate keeps the answer accurate wherever you are.
Is this sales tax calculator accurate and private?
Yes. It uses the standard published formula, shows its working under every result, and computes locally in your browser — your inputs are never sent to a server, and the page works offline.