GST / Sales Tax Calculator

Add tax to a net price or extract the tax from a gross price — with Indian GST presets or any custom rate.

Net amount (before tax)

Tax rate (%)

Net amount

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Tax

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Gross amount

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🔒 Nothing you enter is sent anywhere or stored. All processing happens in your browser.

How it works

GST (Goods and Services Tax) and sales tax are added on top of a product's base price. This calculator handles both directions. In Add tax mode you provide the net (pre-tax) amount and rate, and it shows the tax and the gross total. In Remove tax mode you provide the gross (tax-inclusive) amount, and it works backwards to reveal the original net price and the tax component.

The remove-tax calculation is where people most often slip up. You can't simply subtract the rate from the gross figure — you divide by (1 + rate/100). For an 18% inclusive price of ₹1,180, the net is ₹1,180 ÷ 1.18 = ₹1,000, and the tax is ₹180. Subtracting 18% of ₹1,180 would give the wrong answer.

Quick-select buttons cover India's common GST slabs of 5%, 12%, 18%, and 28%, and you can type any custom rate for VAT or sales tax in other regions. Everything is computed locally, so no invoice data leaves your device.

Examples

Add 18% to ₹1,000 → tax ₹180, gross ₹1,180.

Remove 18% from ₹1,180 → net ₹1,000, tax ₹180.

Custom 7.5% sales tax on $200 → tax $15.00, total $215.00.

Frequently asked questions

How do I remove GST from a total price?

Divide the tax-inclusive amount by (1 + rate/100). For 18%, divide by 1.18. Don't subtract 18% of the gross — that overstates the tax.

What are the Indian GST slabs?

The common rates are 5%, 12%, 18%, and 28%, available as quick-select buttons. Some goods are exempt or use special rates not listed here.

Can I use it for VAT or US sales tax?

Yes. Enter any custom rate in the rate field; the add and remove logic works for any percentage-based tax.

Is this official tax advice?

No. It's a general arithmetic tool. For filing or compliance, check the current rules for your jurisdiction or consult a tax professional.