How do I remove sales tax from a total?

Divide by 1 plus the rate as a decimal. For 8.25%, divide the total by 1.0825. Subtracting 8.25% instead gives a number that is close but wrong.

Which rate should I use?

The combined rate for the exact location of the sale — state plus county plus city plus any special district. It is often more than a point above the headline state rate.

Sales Tax Calculator

Add sales tax to a price, or work backwards from a tax-inclusive total to the pre-tax amount.

Draft — figures checked, awaiting an editorial read. Not indexed.

Total with tax—

Pre-tax amount: —
Tax: —

Formula: Adding: tax = amount × rate ÷ 100. Removing: pre-tax = total ÷ (1 + rate ÷ 100).

What this calculates

This adds sales tax to a price, or removes it from a tax-inclusive total. The removal direction is the one that trips people up and the one that matters for expenses and bookkeeping: to strip 8.25% tax out of a $108.25 total you divide by 1.0825, you do not subtract 8.25%. Subtracting gives $99.32 instead of $100 — close enough to look right and wrong enough to matter across a year of receipts.

How it works

Adding tax multiplies the pre-tax amount by the rate as a decimal and adds the result. Removing tax reverses that: the tax-inclusive total is the pre-tax amount multiplied by one plus the rate, so dividing by that same factor recovers the original price. The asymmetry between the two directions is the whole reason this is worth a calculator rather than mental arithmetic — the operation is not simply reversible by subtraction.

Worked example

A $100 item at 8.25%: tax is 100 × 0.0825 = $8.25, total $108.25. Now working backwards from that $108.25: 108.25 ÷ 1.0825 = $100.00 exactly, with $8.25 of tax. Compare that with naively subtracting 8.25% from $108.25, which gives $99.32 — a 68 cent error on a small purchase, and proportionally the same error on every one after it.

Common mistakes

Subtracting the percentage to remove tax, as above. Second, using a state-level rate when the actual rate is the combined state, county, city and district total — in parts of Alabama, Louisiana and California the combined rate is several points above the state figure. Third, assuming everything in the basket is taxed at the same rate: many US states exempt or reduce tax on groceries, prescriptions and clothing, so a single rate across a mixed receipt will not reconcile. Fourth, using the seller's rate for an online order. Most states apply destination sourcing, meaning the rate is set by where the buyer receives the goods rather than where the seller sits — which is why the same online basket is taxed differently at two delivery addresses in the same state.

Common questions

How do I remove sales tax from a total?: Divide by 1 plus the rate as a decimal. For 8.25%, divide the total by 1.0825. Subtracting 8.25% instead gives a number that is close but wrong.
Which rate should I use?: The combined rate for the exact location of the sale — state plus county plus city plus any special district. It is often more than a point above the headline state rate.