Money & Salary
UK VAT Calculator
Add or remove VAT at 20%, 5%, 0% or a custom rate, correct to the penny.
- Runs in your browser
- 20%, 5%, 0% or custom
What do you want to work out?
Your VAT breakdown
Your breakdown pops up here
Choose add or remove, enter an amount and a rate, then hit Calculate.
You changed something. Hit Calculate to refresh.
How VAT is worked out
r is the VAT rate as a decimal (20% = 0.2). Everything is worked in whole pence, so the breakdown always adds up.
- Add VAT
- Gross = net × (1 + r). £100.00 × 1.2 = £120.00. The net amount is taken to the nearest penny first, the gross is rounded to the nearest penny, and VAT is gross − net.
- Remove VAT
- Net = gross ÷ (1 + r). £120.00 ÷ 1.2 = £100.00. The gross amount is taken to the nearest penny first, the net is rounded to the nearest penny, and VAT is gross − net.
- Rounding
- Half a penny rounds up. Because VAT is the difference between two whole-penny amounts, net + VAT always equals gross exactly.
- The VAT fraction
- The share of a gross price that is VAT: r ÷ (1 + r). At 20% that’s 1/6 of the gross price; at 5% it’s 1/21.
- Which rate applies
- This calculator doesn’t decide which rate your goods or services take. Check GOV.UK for your goods, then pick the rate or enter a custom one.
Questions
How do I remove VAT from a price?
Divide the price including VAT by 1 plus the VAT rate. At 20%, divide by 1.2: £120 ÷ 1.2 = £100 before VAT, so the VAT is £20. Choose “Remove VAT” and the calculator does it for you, to the penny.
Why can’t I just take 20% off a gross price?
Because the 20% was added to the price before VAT, not to the gross price. Taking 20% off £120 gives £96, but the price before VAT was £100. The VAT inside a gross price at 20% is 1/6 of it, not 1/5.
What are the reduced and zero rates for?
The UK has a standard rate, a reduced rate and a zero rate, and which one applies depends on the goods or services. This calculator doesn’t decide that for you: check GOV.UK for your goods, then pick the rate.
What is the VAT fraction?
It’s the share of a gross price that is VAT. At 20% it’s 1/6 of the gross price, and at 5% it’s 1/21. Accountants use it to check invoices quickly.