How to add or remove VAT
- Choose whether your amount excludes tax (you want to add it) or includes tax (you want to know how much of it is tax).
- Enter the amount.
- Pick the country. Its rates appear in the Rate list: standard first, then reduced rates. For anything else, choose Other rate… and type it.
- Read the three figures: the amount before tax, the tax itself and the amount including tax. Each is rounded to the cent, and the tax is always the difference between the other two, so they add up exactly.
How the calculation works
Adding tax is a multiplication: the tax is the net price times the rate, and the gross price is the net plus the tax. Removing tax is where people go wrong. The tax inside a tax-inclusive price is not the price times the rate, because the rate applies to the price before tax. You divide the gross price by one plus the rate to find the net price, and the tax is what is left. At 20%, the tax in a gross price is one sixth of it; at 10%, one eleventh. Australia's GST Act states the rule directly: section 9-70 makes GST 10% of the value of the supply, and the value excludes the GST itself.
Amounts are converted to whole cents and rates to thousandths of a percent before any arithmetic, so results are not disturbed by the binary rounding that makes 0.1 + 0.2 come out as 0.30000000000000004. Halves are rounded up. Real invoices can round differently — per line or per invoice — so a long invoice may differ from a single calculation by a cent or two.
Where the rates come from
Each preset was checked on the date shown under the calculator against an official source: GOV.UK for the UK, the European Commission's Your Europe table for Germany, France, Italy, Spain, the Netherlands and Ireland, Japan's National Tax Agency, the Australian GST Act, New Zealand's Inland Revenue, Singapore's IRAS, the Canada Revenue Agency, and China's VAT Law, in force since 1 January 2026. Rates change: Nova Scotia cut its HST from 15% to 14% on 1 April 2025, for example, and many older rate tables still show 15%.
US sales tax is different
The United States has no national VAT. Sales tax is set by states, and counties and cities often add their own rates on top, so the rate depends on the exact address. Use Other rate… and enter the combined rate for the place of sale. Unlike VAT, US prices are normally shown before sales tax, which is added at the till.
Examples
| Country and rate | Amount | Before tax | Tax | Including tax |
|---|---|---|---|---|
| UK 20% | 100 before tax | 100.00 | 20.00 | 120.00 |
| UK 20% | 120 including tax | 100.00 | 20.00 | 120.00 |
| Australia GST 10% | 110 including tax | 100.00 | 10.00 | 110.00 |
| Australia GST 10% | 99.99 including tax | 90.90 | 9.09 | 99.99 |
| Japan reduced 8% | 1,080 including tax | 1,000.00 | 80.00 | 1,080.00 |
| Quebec GST + QST 14.975% | 100 before tax | 100.00 | 14.98 | 114.98 |
| China 13% | 1,000 including tax | 884.96 | 115.04 | 1,000.00 |
The last row shows the most common mistake: multiplying a tax-inclusive 1,000 by 13% gives 130, which overstates the tax by 14.96. The correct tax inside 1,000 at 13% is 115.04.
Limits
- Which rate applies is up to the rules for each product. The calculator applies the rate you choose; it does not decide whether a product qualifies for a reduced or zero rate.
- Only standard and main reduced rates are preset. Zero rates, exemptions, special regional rates and temporary rates are not listed.
- Rounding on invoices may differ from a single calculation by a cent, depending on whether tax is rounded per line or per invoice.
Frequently asked questions
How do I remove 20% VAT from a price?
Divide the price by 1.2. The tax is the difference: for a price of 120, the net price is 100 and the VAT is 20.
Why is the VAT in a price not simply 20% of it?
Because 20% is charged on the price before tax. The VAT inside a VAT-inclusive price is one sixth of it at 20%.
How much GST is in an Australian price?
One eleventh of the GST-inclusive price, because GST is 10% of the price before GST.
What is the VAT rate in Canada?
Canada has a 5% GST, replaced by a harmonised sales tax in five provinces: 13% in Ontario, 14% in Nova Scotia and 15% in New Brunswick, Newfoundland and Labrador and Prince Edward Island.
Are my amounts stored?
No. Everything is calculated in your browser.