GST Calculator
Add GST to a price, or take GST out of a price that already includes it. See CGST + SGST for a sale within your state, or IGST for a sale to another state.
0.25, 3, 5, 18 and 40 % are the slabs from 22 September 2025; 12 and 28 % appear on older bills. Check the rate for your HSN/SAC with your CA or the CBIC rate notification.
Result
How it works
Add GST
GST = amount × rate. Total = amount + GST. Example: ₹1,000 at 18 % = ₹180 GST, total ₹1,180.
Remove GST
Taxable value = price ÷ (1 + rate). Example: ₹1,180 including 18 % = ₹1,000 taxable value and ₹180 GST.
CGST, SGST or IGST
Within your state, GST is split in half: CGST + SGST. To another state, it is one IGST at the full rate.
Amounts are rounded to the paisa, half up. These are the same calculations BoostBizTools uses on GST invoices.
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