GST Calculator

Add or remove GST from an amount, at any slab rate — as you type.

Use this if you know the price before GST.

%

Within Same State → CGST + SGST

GST AmountEnter an amount and GST rate to calculate

What is GST?

GST (Goods and Services Tax) is a single indirect tax applied to most goods and services sold in India, replacing the earlier patchwork of separate state and central taxes since it was implemented on July 1, 2017. It's charged as a percentage of the price, at a rate that depends on what's being sold.

Why use this calculator?

Sellers usually need to go from a base price to a GST-inclusive price; buyers or accountants often need the opposite — working backwards from a GST-inclusive total to find the base price and how much of that total was tax. This calculator does both directions, and shows the CGST/SGST or IGST split so the breakdown matches how the tax is actually billed on an invoice.

Worked Example — ₹10,000 at 18% GST

Add GST (within state)₹10,000.00 + 18%₹11,800.00CGST ₹900.00 + SGST ₹900.00
Remove GST (within state)₹11,800.00 incl. 18%₹10,000.00base price, GST removed
Add and Remove are exact inverses of each other — the same ₹10,000.00 base and ₹11,800.00 inclusive total either way. An inter-state version of the same transaction shows the identical ₹1,800.00 as a single IGST line instead of split CGST + SGST.

Common GST Rates in India

The standard slabs this calculator's preset chips use — confirm the actual rate for what you're billing rather than assuming 18%.

RateTypical for
0%Exempt goods — unbranded food staples, books, fresh produce
5%Essential household items, packaged food, footwear under ₹1,000
12%Processed food, business inputs, computers
18%Standard rate — most goods and services fall here
28%Luxury and sin goods — cars, tobacco, aerated drinks

Some categories fall outside these five slabs — gold and gold jewellery, for example, are taxed at 3%, not one of the preset chips. Type the rate directly into the GST Rate field for any rate not shown as a chip.

Frequently Asked Questions

An amount that doesn't yet include GST — the base price before tax is added. This calculator's "Add GST" mode starts from a GST-exclusive amount; "Remove GST" does the reverse, taking a GST-inclusive amount and finding the GST-exclusive base price within it.

Common Mistakes to Avoid

  • Don't apply the rate to a GST-inclusive amount. If your number already includes GST, use Remove GST — multiplying an inclusive amount by the rate directly double-counts the tax already baked in.
  • CGST + SGST and IGST are the same total tax, not extra tax. Within-state splits the GST amount evenly into CGST and SGST; inter-state charges the identical total as one IGST line. Switching the toggle changes the breakdown, not the amount you pay.
  • Not everything is 18%. 18% is the most common slab, but essentials can be 0% or 5%, and luxury/sin goods go up to 28% — always confirm the actual rate for what you're billing, don't assume the default.

References

  • Central Board of Indirect Taxes and Customs (CBIC)
  • Goods and Services Tax Council, Government of India

Last reviewed July 2026

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