Sales Tax, VAT & GST Calculator
Choose whether your price excludes tax (add it) or already includes tax (extract it) - works for US-style sales tax added at checkout or VAT/GST already built into a displayed price.
Last updated: September 22, 2026
Frequently asked questions
How do I calculate sales tax on a purchase?
Multiply the price by the tax rate as a decimal, then add that to the original price. For $49.99 at 7.25% tax: $49.99 × 0.0725 = $3.62 tax, for a total of $53.61. Select "Excludes tax" above for this direction.
How do I extract VAT or GST from a price that already includes it?
Select "Already includes tax" above, enter the tax-inclusive price and the rate, and the calculator divides by (1 + tax rate) to find the pre-tax base price - for example, a $110 price with 10% GST already included has a $100 base price and $10 of tax, not $11 of tax (which is what you'd get by mistakenly multiplying instead of dividing).
What's the difference between sales tax and VAT/GST for this calculator?
The math for adding tax is identical - both apply a percentage rate to a price. The practical difference is which direction you usually need: US sales tax is typically added on top of a displayed price at checkout ("excludes tax" mode), while VAT and GST prices are usually displayed already including the tax, so you more often need to extract it ("already includes tax" mode) to see the pre-tax amount, e.g. for expense reporting or accounting.
Does sales tax rate vary by location?
Yes - sales tax rates are set by state, county, and sometimes city, so the combined rate can vary significantly even within the same state. VAT and GST rates instead vary by country (and sometimes by product category within a country) rather than by sub-national jurisdiction. Check your specific local or national rate before relying on a default.
Is sales tax calculated on the price before or after other discounts?
Sales tax is almost always calculated on the final sale price after discounts are applied, not on the original list price - so apply any discount first, then calculate tax on the reduced amount.
Are groceries and clothing always taxed at the same rate as other purchases?
No - many jurisdictions exempt or reduce the tax rate on groceries, prescription medication, and sometimes clothing, while taxing general merchandise at the standard rate. Check your local tax authority's rules if you're calculating tax for a specific exempt category rather than a general purchase.
I need this for an invoice - does "extract tax" work for that?
Yes - an invoice showing a tax-inclusive total (common outside the US) is exactly what "Already includes tax" mode is for: enter the gross (total, tax-inclusive) amount and rate, and the calculator returns the net (pre-tax) amount and the tax portion separately, which is what most invoicing and bookkeeping needs require.