Sales Tax Calculator
Add sales tax to any amount or work backwards from a tax-inclusive total to the pre-tax price. Enter your own local rate.
- Pre-tax amount
- $100.00
- Sales tax
- $8.50
- Total
- $108.50
Estimates only, not tax advice. Tax rates vary by location — enter the combined state and local rate that applies to you.
How sales tax works
Sales tax is a percentage added on top of a purchase price. To add tax, multiply the pre-tax amount by the rate and add it back: $100 at 8.5% becomes $8.50 in tax and a $108.50 total. To remove tax from a receipt total, divide by (1 + rate) — $108.50 ÷ 1.085 = $100.00 before tax.
Because US sales tax is set by states, counties, and cities, there is no single national rate. Enter the combined rate that applies where the sale happens and both directions stay accurate.
Estimates only, not tax advice. Tax rates vary by location and can change. Verify the current combined rate for your jurisdiction before relying on these figures.
FAQ
How do I calculate sales tax on a purchase?▾
Multiply the pre-tax amount by the tax rate as a decimal, then add it back. At an 8.5% rate, a $100 purchase has $8.50 in tax for a $108.50 total. Enter the amount and your local rate above to see it instantly.
How do I work out the price before tax from a total?▾
Switch to "Remove tax" mode. The pre-tax price is the total divided by (1 + rate). A $108.50 total at 8.5% works back to $100.00 before tax.
What sales tax rate should I enter?▾
Use the combined rate for your location — the state rate plus any county or city rates that apply. Rates vary widely, from 0% in a few states to over 10% in some cities, so check your local rate.
Does this calculator know my local tax rate automatically?▾
No. It does not look up rates by address or ZIP code. You enter the rate yourself, which keeps it accurate for any state, county, or special district as long as you supply the correct combined rate.
Can I use this for VAT or GST?▾
Yes — the math is the same for any percentage-based consumption tax. Enter your VAT or GST rate in the rate field and the add/remove modes work identically.