GSTIN checker
Type a GST number from an invoice. See if it's correctly formed, which state it's from and whose PAN it carries.
- Official state codes
- Checks the last character
- Free, no sign-up
A valid GSTIN isn't the whole story
Your input tax credit depends on the supplier filing their returns. Our experts check it before you claim.
Questions people often ask
The GSTIN is valid. Is the supplier genuine?
Not necessarily. Check the name and status on the GST portal, and that their invoices appear in your GSTR-2B.
What if an invoice has the wrong GSTIN?
Ask the supplier to issue a credit note and a corrected invoice, or the credit won't reach your GSTR-2B.
How to read a GSTIN
15 characters, five parts.
- 1–2: the state code, such as 29 for Karnataka.
- 3–12: the holder's PAN.
- 13: the registration number for that PAN in the state.
- 14: Z, by default.
- 15: a check character worked out from the first 14.
Last reviewed 9 October 2026. The rules in this calculator come from these official sources.
- GST portal: Search Taxpayer Goods and Services Tax Network
- Master codes: GST state codes GST e-invoice system (NIC)
- Permanent Account Number (PAN) Income Tax Department
Common questions
How do I check if a GST number is valid?
Enter it above. We check its length, state code, the PAN inside it and the check character. To confirm the business name and that it's active, use Search Taxpayer on the GST portal.
What does each part of a GSTIN mean?
The first 2 digits are the state code, the next 10 are the holder's PAN, the 13th is the registration number for that PAN in the state, the 14th is Z by default, and the 15th is a check character.
What is the check character?
The last character is worked out from the first 14 by a fixed formula. If one character is mistyped or two are swapped, it almost always stops matching.
Why does 22AAAAA0000A1Z5 show as not valid?
It's a sample often copied online to show the format, but its check character works out to C, not 5. 22AAAAA0000A1ZC is the correctly formed version.
Can I find the business name from the GSTIN?
Not from the number alone. The GST portal's Search Taxpayer shows the legal name, address, status and filing history.
Is my GSTIN sent anywhere?
No. The check runs in your browser and nothing you type is sent to us or anyone else.