%GST Calculator Pro
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Tax Percentage Calculator

Find the effective tax rate hiding between two prices, or apply any percentage to an amount — for GST, VAT and every other percentage charge.

Work with any tax percentage

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Note: Results are for quick estimation and general information only, based on rates as commonly applicable in 2026. Always confirm figures with the official GST/Income Tax portals or a qualified professional before filing. See our full disclaimer.

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How to calculate a tax percentage

Two everyday problems, one tool. Find the rate: you know the price before and after tax and want the effective percentage — useful for checking a bill or comparing quotes. Apply a rate: you know the amount and the percentage and want the tax and total.

Tax % = (Price after − Price before) ÷ Price before × 100
Tax amount = Amount × Rate ÷ 100

Example: if a quote of ₹1,000 becomes ₹1,180 on the invoice, the effective tax is (180 ÷ 1,000) × 100 = 18%. This works for GST, VAT on fuel, professional tax, or any percentage-based charge.

Frequently asked questions

How do I find what tax percentage was charged?

Subtract the pre-tax price from the final price, divide by the pre-tax price, and multiply by 100. Our 'Find the tax %' mode does this instantly.

Can I use this for taxes other than GST?

Yes — it is a general percentage tool. Use it for VAT on petrol and diesel, professional tax comparisons, service charges or any percentage markup.