Your figures
Result
How this calculator works
Choose a direction first. Adding VAT takes a net amount, applies the rate, and gives you the tax and the gross total your invoice should show. Removing VAT works backwards from a price that already includes tax — a shelf price, a receipt total — and separates it into the net amount and the VAT inside it. Both directions show all three figures, because invoices, accounts and returns all want the same trio stated explicitly.
The removal direction is the one people get wrong by hand. VAT is charged on the net, so the tax inside a gross figure is found by dividing by one plus the rate — a 120 total at 20% contains 20 of VAT, not 24. Subtracting 20% of 120 double-counts, and the error ends up in the return. This calculator exists largely to make that one mistake impossible.
Good practice and limits
Keep the rate per product line, not per business: many VAT systems run several rates at once (a standard rate, reduced rates, zero-rating and exemptions), and a single blended rate in your head will drift from all of them. Zero-rated and exempt are also not the same thing — zero-rating is a taxable supply at 0% that still allows input VAT recovery, exemption usually does not.