Sales Tax / VAT Calculator (add tax or extract from total)

Add tax vs extract tax

Adding tax: you have the price before tax and want the final price. Multiply by (1 + rate/100). Example: $100 at 8% sales tax = $108.

Extracting tax: you have the total a customer paid (or saw on the receipt) and need to reverse-engineer how much was tax. Divide the total by (1 + rate/100) to get the pre-tax amount; the difference is the tax. Example: $108 at 8% extracts to $100 + $8 tax. Don't multiply $108 by 8% — that gives $8.64, which is wrong.

Sales tax, VAT, and GST

Sales tax (US): added at the point of sale, varies by state and city. New York City is 8.875%, Oregon has none, California ranges 7.25-10.75% depending on city. Many US prices are advertised pre-tax and tax is added at checkout.

VAT (EU, UK): typically already included in the displayed price. UK standard rate is 20%, France is 20%, Germany is 19%. Use 'extract from total' to find the tax in a quoted price.

GST (Australia, NZ, Canada, India): a single national rate (Australia and NZ at 10% and 15% respectively, Canada has GST plus provincial taxes). India uses tiered GST rates (5/12/18/28%) by product category.

Common pitfalls

Don't multiply tax-inclusive totals by the rate. To extract tax from $108 at 8%, divide by 1.08 first. Multiplying by 8% gives the wrong answer because the $108 already includes the 8% on the original $100 — and you'd be taxing the tax.

Some products are exempt or zero-rated (groceries in many US states; books in the EU at reduced rate; etc.). When advertising prices including/excluding tax, follow your jurisdiction's rules.