Calculate GST amount, and add or remove GST from any price.
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No limits, no payment, ever
Fill in the required numbers in the calculator.
The result updates automatically as you type.
Review the detailed breakdown shown below the result.
This calculator is free and has no usage limit.
GST Calculator helps you quickly work out the Goods and Services Tax amount on any price — either add GST to a base amount or extract GST from a GST-inclusive amount.
From 22 September 2025 most goods and services fall in two slabs — 5% and 18%. A 40% rate applies to luxury and sin goods, and gold stays at 3%. The earlier 12% and 28% slabs were merged into these.
Yes, completely free with no sign-up required and no limit on how many times you can use it.
No. All calculations happen instantly in your browser — nothing is sent to any server.
Add GST calculates the final price when GST is added on top of a base price. Remove GST extracts the base price and GST amount from a price that already includes GST.