GSTIN validator

Paste a GST number (GSTIN) to check that it's correctly formed: 15 characters, a valid state code, a PAN in the middle and a matching check digit. A wrong check digit almost always means a typo. The tool works offline, so it can't tell whether the registration is active; for that, search the GSTIN on gst.gov.in.

Free, no sign-up Runs in your browser

How a GSTIN is built

Every GST registration in India gets a 15-character Goods and Services Tax Identification Number:

CharactersMeaningExample (27AAPFU0939F1ZV)
1–2State code27 = Maharashtra
3–12PAN of the business or personAAPFU0939F
13Registration number under that PAN in the state (1–9, then A–Z)1 = first registration
14"Z" by defaultZ
15Check digit, calculated from the first 14 charactersV

The 4th character of the PAN shows the type of holder: P individual, C company, H HUF, F firm, T trust, and so on. The validator shows this for you.

How the check digit works

Each of the first 14 characters is turned into a number (0–9 stay as they are, A = 10 … Z = 35). Every second character is doubled; each product is split into its quotient and remainder by 36, and all of those are added up. The check digit is whatever brings the total to a multiple of 36. A single mistyped character or two swapped neighbouring characters almost always produce the wrong check digit, which is why this check catches most typos.

What this check can and can't tell you

  • It can confirm the GSTIN is correctly formed, catch typos, and show the state and PAN inside it.
  • It can't confirm that the registration exists, is active, or belongs to the business you're dealing with. A made-up number can still have a valid check digit.
  • To verify a supplier before claiming input tax credit, use Search Taxpayer on the official GST portal (gst.gov.in), which shows the legal name, status and filing history.

State codes

CodeStateCodeState
07Delhi27Maharashtra
09Uttar Pradesh29Karnataka
19West Bengal32Kerala
24Gujarat33Tamil Nadu
06Haryana36Telangana
08Rajasthan37Andhra Pradesh

The validator knows every state and union territory code. To put a GSTIN on a bill, use the GST invoice generator, which reads the state from the GSTIN for you.

Frequently asked questions

How do I check if a GSTIN is valid?
Paste it above. The tool checks the length, state code, PAN structure and check digit. To confirm the business is actually registered and active, also search it on the official GST portal.
What does each part of a GSTIN mean?
Two digits for the state, the 10-character PAN, one character for the registration number under that PAN, the letter Z, and a check digit.
Can I find the PAN from a GSTIN?
Yes. Characters 3 to 12 of a GSTIN are the holder's PAN. The validator shows it, along with the type of holder from the PAN's 4th character.
Why does a GSTIN fail the check digit test?
Usually a typo: a wrong or swapped character, or a letter O typed for a zero. Ask the supplier to confirm the number from their registration certificate.
Is my data sent anywhere?
No. The checks run in your browser and nothing is looked up online. That's also why the tool can't tell you whether a registration is active.

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