GSTIN Validator
Check whether a GSTIN is correctly formatted and passes its check-digit. Works offline.
- State code
- PAN
About this tool
Check whether a GSTIN is valid by verifying both its 15-character format and its built-in check digit. Useful before adding a vendor or customer GSTIN to your invoices. It works entirely offline — no API and no lookups.
How to use it
- 1 Paste or type the 15-character GSTIN.
- 2 See instantly whether the format and check digit are valid.
- 3 View the embedded state code and PAN.
Frequently asked questions
Does this confirm the GSTIN is registered and active?
No. It mathematically validates the format and check digit. To confirm a GSTIN is actively registered, check the official GST portal.
How does the check work?
A GSTIN’s 15th character is a checksum computed from the first 14. This tool recomputes it and compares — a mismatch means the number is invalid.
Is the GSTIN I enter sent anywhere?
No, validation is purely algorithmic and runs offline in your browser.