Sales tax calculator (add or remove tax)
Add sales tax to a price, or work out the price before tax from a total, at the rate you enter.
What does the VAT calculator do?
This VAT calculator works in both directions: add VAT to a net price, or remove it from a price that already includes it (a reverse VAT calculation). Pick a preset rate or type any percentage; the same maths works for GST and similar taxes.
How to use the VAT calculator
- Choose “Add VAT” if your price excludes VAT, or “Remove VAT” if it already includes it.
- Enter the amount.
- Select a rate or type a custom percentage.
- Read the net amount, VAT amount and gross total, and copy any figure with one click.
Your privacy
Calculations happen in your browser. No amounts are uploaded or stored.
Frequently asked questions
How do I add VAT to a price?
Multiply the net price by (1 + rate ÷ 100). At 20%, a net price of 100 becomes 100 × 1.2 = 120.
How does a reverse VAT calculation work?
Divide the gross price by (1 + rate ÷ 100). At 20%, 120 ÷ 1.2 = 100 net, so the VAT included is 20. Simply taking 20% off 120 gives the wrong answer (96).
Can I use this as a UK VAT calculator?
Yes. The 20% preset matches the UK standard rate and the 5% preset matches the reduced rate at the time of writing. Rates can change and some goods are zero-rated or exempt, so check GOV.UK for what applies to you.
Does it work as a GST calculator?
Yes. GST and similar sales taxes use the same arithmetic. Enter your GST rate as a custom percentage and choose whether to add or remove it.
Is this tax advice?
No. This is a general arithmetic tool. For questions about registration, exemptions or what to charge, speak to an accountant or your local tax authority.