GST / VAT Calculator
Add or remove a user-entered GST, VAT or sales tax rate from an amount. Tax rates vary by location and product; verify the applicable rate before use.
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Sample inputs to see how the calculator works
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Complete the fields above to see your result. You can change any value at any time.
Understanding GST / VAT Calculator
How to add or remove a consumption tax
To add a tax, the calculator applies the selected percentage to the pre-tax amount. To remove tax from a tax-inclusive total, it backs out the tax using the inclusive amount and the selected rate; simply subtracting the rate percentage from the total would give a different result.
GST, VAT and sales-tax systems can have different rates, exemptions, rounding conventions and rules for tax-inclusive prices. Choose the rate that applies to your transaction and confirm whether the displayed calculation matches local requirements.
What this estimate does not decide
The calculator performs the arithmetic for the rate you enter. It does not determine whether a supply is taxable, which rate legally applies, whether input tax credits are available, or how a business should report the transaction.
For invoices, filings or cross-border transactions, check the applicable tax authority's rules and the treatment required for your specific supply.
Calculation methodology
GST is calculated by applying the entered rate to the base amount, or by backing the GST component out of a GST-inclusive amount.
Important assumptions
- Results are estimates based on the values you enter.
- Rates and returns are assumed for the projection period and may change in real life.
- Taxes, fees, market conditions and provider-specific rules may affect actual outcomes.
GST rate source
The rate is entered by you; this calculator does not select a product-specific GST rate or decide place-of-supply treatment.
Sources checked October 2, 2026. Rates and scheme terms are not live-updated.
GST / VAT Calculator for clearer money decisions
Add or remove a user-entered GST, VAT or sales tax rate from an amount. Tax rates vary by location and product; verify the applicable rate before use.
The calculator runs in your browser — nothing is stored on our servers. Switch between INR and USD at the top right of the workspace to see values in your preferred currency. Compare two sets of assumptions side by side.
How do I add GST to an amount?
Enter the base amount and GST rate. The calculator adds the selected percentage to estimate the tax-inclusive total.
How do I calculate tax included in a total?
Divide the tax-inclusive total by 1 plus the tax rate expressed as a decimal to estimate the pre-tax amount. The difference is the included tax, before any required rounding rules.
Does the calculator determine the correct tax rate?
No. You must enter the rate appropriate to the supply and jurisdiction. Confirm classifications and current rules with the relevant tax authority.
How do I remove GST from a total?
Enter the tax-inclusive total and the GST rate. The calculator estimates the pre-tax amount by reversing the percentage calculation.
Can I use this for GST, VAT or sales tax?
You can use it for the arithmetic of a rate you enter, but legal treatment and rounding rules vary. It does not determine which rate or exemption applies to a transaction.
Does this calculate business tax credits or returns?
No. It estimates tax added to or removed from an amount and does not calculate input credits, tax returns or wider compliance obligations.
Educational estimate only. Not investment, tax or legal advice. Please verify current rates, slabs, taxes, fees and rules before making a financial decision.