Sales Tax Calculator

Sales tax is a percentage-based tax added to the price of goods and services at the point of sale. It goes by different names around the world — sales tax in the US, VAT (Value Added Tax) in the UK and Europe, and GST (Goods and Services Tax) in Canada, Australia and elsewhere — but the everyday math is the same: a set percentage of the price is added on top, and the seller collects it for the government.

Calculating it is simple. To add tax, multiply the price by the tax rate and add the result to the price; a $100 item at an 8% rate carries $8 of tax for a $108 total. The total can also be found in one step by multiplying the price by (1 + rate). This forward calculation is what you need when pricing a sale or estimating the cost of a purchase.

The reverse calculation is just as useful and more often misunderstood. When you have a tax-inclusive total and want to know how much of it is tax — for an expense report, a VAT return or bookkeeping — you can't simply take the percentage of the total. Instead you divide the total by (1 + rate) to get the pre-tax price, then subtract to find the tax. For example, $108 including 8% tax contains $8 of tax, not $8.64. Getting this right matters for accurate accounting.

Rates vary enormously by location and product. In the US, sales tax is set by states and localities, so it differs from one city to the next and some items are exempt; many countries apply a single national VAT/GST rate with reduced rates for essentials. Some prices are shown tax-inclusive (common in the UK and EU) and others tax-exclusive (common in the US), which is why knowing both the forward and reverse calculation is handy.

This calculator handles any rate you enter, so it works for US sales tax, VAT, GST or any other percentage-based tax. Always check the correct rate for your location and the specific item, as exemptions and reduced rates are common.