Math, Science & Calculators · Free Tool

GST / VAT Calculator

Add or remove GST / VAT / sales tax at any rate — see the net amount, the tax, and the gross total. Quick rate presets and live results, all in your browser.

Amount (net)

Tax rate %

Net

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Tax

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Gross

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How it works

Adding tax multiplies the net amount by the rate to get the tax, then adds it for the gross. Removing tax works backwards: the amount you enter already includes tax, so the net is gross ÷ (1 + rate), and the tax is the difference. The same maths covers GST, VAT and sales tax — only the rate changes.