Sales Tax Calculator
Add sales tax to any amount and see the tax and final total.
How to use
- Enter the pre-tax amount.
- Enter your local sales tax (or VAT) rate.
- See the tax owed and the final total.
How the Sales Tax Calculator works
Adds sales tax to a price, or works backwards from a tax-inclusive total to recover the pre-tax amount.
Forward is a simple percentage addition. Reverse requires division rather than subtracting the percentage — a common and costly mistake.
total = price × (1 + rate), price = total / (1 + rate)
Worked example
$100 at 8.25% is $108.25. Going the other way, $108.25 including 8.25% tax is $108.25 / 1.0825 = $100 — not $108.25 − 8.25%, which would wrongly give $99.32.
Things worth knowing
- US sales tax is set locally, so state, county and city rates stack. The combined rate can differ between neighbouring streets.
- Sales tax is added at the register in the US. VAT and GST elsewhere are usually already inside the displayed price.
Frequently asked questions
How do I calculate sales tax?
Multiply the amount by the tax rate divided by 100, then add it back to the original amount for the total.
Does this work for VAT or GST?
Yes — enter your VAT or GST percentage in the rate field.
How do I remove tax from a total?
Divide by 1 plus the rate. Subtracting the percentage gives the wrong answer because the percentage was applied to the smaller pre-tax figure.
Why do online orders show different tax rates?
Sales tax is generally charged at the delivery address, so the rate follows the destination rather than the seller.