Sales tax, VAT and GST calculator
One rate, two directions: add tax onto a price that excludes it, or work out how much tax is already inside a price that includes it.
If the amount excludes tax
- Net (before tax)
- 1,000.00
- Tax at 15%
- 150.00
- Gross (with tax)
- 1,150.00
If the amount already includes tax
- Gross (as entered)
- 1,000.00
- Tax at 15%
- 130.43
- Net (before tax)
- 869.57
The two formulas
Adding tax is simple multiplication: net × (1 + rate). Removing it is the part people get wrong — you divide rather than subtract, because the tax was charged on the net figure, not on the gross one. Taking 15% off a gross price is not the same as the 15% that was added to the net price.
Which rate should you enter?
That depends on where you're registered, what you sell and who you're selling to. Rates change, reduced and zero rates exist for some goods and services, and cross-border sales have their own treatment. Use the rate your own registration or your accountant tells you to use — this tool deliberately doesn't preset one, and nothing here is tax advice.
Putting it on a document
Invoices generally show the net amount, the tax as a separate line and the gross total, so the customer can see what was charged. The invoice generator lays it out that way automatically, and the tax invoice template covers what a tax invoice usually has to show.