Reverse VAT Calculator
Remove VAT from a VAT-inclusive amount.
What this tool calculates
Reverse VAT Calculator is designed to give a direct answer from the values entered above. The main inputs on this page are Gross amount (£), VAT rate (%). The result is intended to be readable immediately, with the explanation below available when you need to verify the method.
Method and calculation basis
To add VAT, gross = net × (1 + rate). To extract VAT from a VAT-inclusive amount, net = gross ÷ (1 + rate) and VAT = gross − net. Simply subtracting the VAT percentage from a gross price is not the reverse calculation.
Worked examples
Add 20% VAT
£100 net becomes £120 gross.
Extract 20% VAT
£120 gross ÷ 1.20 = £100 net, so VAT is £20.
Understanding the result
The output should be read in the units shown beside the result. If you are comparing alternatives, keep all unchanged assumptions identical and alter one input at a time. That makes it easier to see which value is responsible for the difference.
Assumptions, edge cases and accuracy
Prices, tax treatment and statutory rules can change. Where the tool relates to tax or payroll, verify the applicable tax year and current official guidance before making a financial decision.
Sources and methodology
- HM Revenue & Customs (HMRC) — Current UK tax and VAT rules where applicable
- UK Government / GOV.UK — Statutory rates and official guidance
Method reviewed for Instant Solvers V10.0 · October 2026. If you find a calculation or explanation that needs correcting, use the site Contact page and include the tool URL and the values you entered.