Sales Tax and VAT Calculator
Add tax to a price, or work out the tax already included in it.
About this tool
Adds tax by multiplying the price by (1 + rate), or removes it by dividing a tax-inclusive price by (1 + rate). Works for VAT, GST and US sales tax at any rate.
Whether you are quoting a customer, checking a receipt or budgeting for a purchase, you often need to add tax to a price or find the tax hidden inside one. Choose whether to add or remove tax, enter the price and the rate, and the calculator shows the price before tax, the tax itself and the total. It works for VAT, GST and sales tax at any rate.
How to use the Sales Tax and VAT Calculator
- Choose whether to add tax to a price or remove it from a price that includes tax.
- Enter the price.
- Enter the tax rate as a percentage, for example 15 for 15%.
- Read the price before tax, the tax and the total.
Adding and removing 15% VAT
Adding 15% to 100 gives 15 in tax and 115 in total. Removing 15% from a price of 115 is not 115 minus 15%: it is 115 ÷ 1.15 = 100 before tax, so the tax is 15. Taking 15% off 115 would wrongly give 97.75, which is why the calculator divides instead.
Why removing tax means dividing
Tax is charged on the price before tax, so a tax-inclusive price is that price times (1 + rate). To get back to the original, divide by (1 + rate). The tax inside an inclusive price is the total × rate ÷ (100 + rate); at 15% that is 3 ÷ 23 of the total, about 13.04%. VAT and GST are added at every stage of supply and shown on invoices, while US sales tax is added only at the final sale, at a combined state and local rate that varies by city and county. Rates differ widely: South Africa charges 15% VAT, the UK 20% standard rate, Australia 10% GST, and many US states between 4% and 10% sales tax.
Frequently asked questions
How do I calculate the VAT in a price?
Divide the price by 1 plus the rate as a decimal, then subtract that from the price. At 15%, the VAT in 230 is 230 − 230 ÷ 1.15 = 30.
Is removing 15% the same as taking 15% off?
No. Taking 15% off a VAT-inclusive price removes too much. You must divide by 1.15.
What rate should I use?
Use the rate that applies where the sale happens. For US sales tax, combine the state and local rates.
Does this round like an invoice?
Results are shown to two decimals. Invoices may round tax per line, which can differ by a cent.