Free GST utility
GST Calculator & GSTIN Format Checker
Calculate inclusive or exclusive GST, view CGST/SGST or IGST splits, and perform a basic GSTIN format check.
GST Calculator
Calculate GST for an amount that is either before tax or already inclusive of tax.
Taxable value₹1,000.00
CGST (9%)₹90.00
SGST (9%)₹90.00
Total GST₹180.00
Invoice value₹1,180.00
GSTIN Format Checker
This checks the GSTIN structure locally. It does not confirm registration status with the GST portal.
- 15-character GSTIN pattern check
- Basic Indian state-code range check
- No GSTIN is transmitted or stored by this tool
How this GST calculator works
For GST-exclusive prices, tax is added to the taxable value. For GST-inclusive prices, the taxable value is derived from the final amount. Select CGST + SGST for an intra-state split or IGST for an inter-state calculation.
Important: the GSTIN checker only validates the expected 15-character format and a basic state-code range. It is not an official GST registration lookup and should not be used as proof that a GSTIN is active.