Question 1

How do I calculate sales tax?

Accepted Answer

Multiply the pre-tax price by the tax rate (as a decimal). For example, $50 with 8% tax: $50 × 0.08 = $4.00 tax, total $54.00. The 'Add Tax' tab does this automatically.

Question 2

How do I find the pre-tax price from a total?

Accepted Answer

Divide the total by (1 + tax rate). Example: $54 with 8% tax → $54 ÷ 1.08 = $50.00 pre-tax, $4.00 tax. Use the 'Reverse Tax' tab.

Question 3

What sales tax rate should I use?

Accepted Answer

Use your combined state + local rate. State sales tax ranges from 0% (e.g. Oregon, Delaware) to 7.25% (California). Cities and counties often add 0.5%–4% on top, so combined rates can reach 9–10% in some places.

Sales Tax Calculator

Add sales tax to a price

Formulas