Free tool

GST Calculator — add or remove GST instantly

Enter an amount and a GST rate to see the tax, the CGST + SGST or IGST breakup, and the final amount.

GST rate (%)
Amount is
Type of sale
Amount before GST
₹1,000.00
CGST (9%)
₹90.00
SGST (9%)
₹90.00
Total GST
₹180.00
Total amount
₹1,180.00

Billing every day? Effy Order applies the right GST to every invoice automatically, based on HSN code and customer state.

Frequently asked questions

How do I add GST to an amount?

Multiply the amount by the GST rate and divide by 100 to get the GST. Add it to the amount for the total. For example, ₹1,000 at 18% GST is ₹180 GST, so the total is ₹1,180.

How do I remove GST from an amount that already includes it?

Divide the GST-inclusive amount by (1 + rate/100) to get the amount before tax. For example, ₹1,180 including 18% GST is ₹1,000 before tax and ₹180 GST.

When is CGST + SGST charged and when is IGST charged?

For a sale within the same state (intra-state), GST is split equally into CGST and SGST. For a sale to another state (inter-state), the full GST is charged as IGST.

Can Effy Order calculate GST on my invoices automatically?

Yes. Set your GST rate per HSN code once and Effy Order applies the correct CGST, SGST or IGST on every invoice.

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