GST Calculator
Original Amount (Rs.)
GST Rate
Original Amount
GST Amount
Total (with GST)
Amount (incl. GST) (Rs.)
GST Rate
Total (incl. GST)
GST Amount
Original (excl. GST)
Original Amount (Rs.)
GST Rate
Original Amount
CGST (@%)
SGST (@%)
Total GST
Total Payable
How to Calculate GST
1Add GST: GST Amount = Original x (Rate/100). Total = Original + GST. Example: Rs.1000 at 18% = Rs.180 GST, Total = Rs.1180
2Remove GST: Original = Total / (1 + Rate/100). Example: Rs.1180 at 18% = Rs.1000 original
3CGST & SGST: Each is half the total GST. At 18%: CGST = 9%, SGST = 9%. Example: Rs.1000 → CGST = Rs.90, SGST = Rs.90
4IGST applies on interstate supply — equal to the full GST rate, not split.
Formulas:
GST Amount = Amount x Rate / 100
Price + GST = Amount x (1 + Rate/100)
Price excl. GST = Total / (1 + Rate/100)
CGST = SGST = GST Amount / 2
GST Amount = Amount x Rate / 100
Price + GST = Amount x (1 + Rate/100)
Price excl. GST = Total / (1 + Rate/100)
CGST = SGST = GST Amount / 2