Add sales tax to a shelf price, or strip the tax back out of a total you were quoted. Give the amount and the rate — you get the net price, the tax itself and the gross total in one pass.
Estimates only. This tool is provided for educational purposes and is not financial advice. It models the figures you enter — it does not know your credit terms, local taxes, or fees. Talk to a licensed adviser before making a decision.
A shelf price of $100 with an 8.25% rate adds $8.25 of tax for a $108.25 checkout total. Switch to reverse, enter $108.25, and the same rate returns a net price of $100.00 and tax of $8.25.
Going forwards is simple multiplication. Going backwards is not division by the same number — you must divide by one plus the rate, otherwise you overstate the pre-tax price and understate the tax.
Gross = Net × (1 + rate) · Net = Gross ÷ (1 + rate)
Tax = Gross − Net
Taking 8.25% off a $108.25 total gives $99.32 — close, but wrong. The $8.25 of tax was charged on the $100 net price, not on the $108.25 gross. The error grows with the rate: at 20% the shortcut is out by more than two dollars on a hundred.
There is no national sales tax. Rates are set by state, county, city and sometimes special district, and they stack. That is why the same purchase can cost different amounts ten miles apart.
How do I add sales tax to a price?
Multiply the net price by one plus the rate. At 8.25%, $100 becomes $108.25. Enter the price in Add mode and the calculator does it for you.
How do I remove sales tax from a total?
Divide the gross total by one plus the rate — not subtract the rate. $108.25 ÷ 1.0825 gives $100.00 net and $8.25 tax. Use Reverse mode.
Why is reverse tax not just subtracting the percentage?
Because the tax was charged on the smaller net amount. Subtracting the rate from the gross overstates the original price and understates the tax. The error grows as the rate rises.
What sales tax rate should I use?
Use the combined rate on your receipt, which blends state, county and city rates. Ranges run from 0% in five states to above 10% in parts of California, Illinois and Louisiana.
Is sales tax the same as VAT?
No. Sales tax is added once at the final sale and is quoted exclusive of tax in the US. VAT is collected at every stage of the supply chain and EU and UK prices are usually shown tax-inclusive.