Free tool
GSTIN validator
Check GSTIN format and checksum offline. Extract state, PAN, and entity number before you invoice.
Format check
Offline checksum validation · Does not query GST portal
Format: state (2) + PAN (10) + entity + Z + checksum ·
Validate GSTIN on every invoice — offline
PocketGST checks customer and vendor GSTIN format while you bill. No portal lookup needed for day-to-day format checks.
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GSTIN format explained
27AAAAA0000A1Z5
State (2) + PAN (10) + Entity (1) + Z + Checksum (1)
| Position | Meaning | Example |
|---|---|---|
| 1–2 | State code | 27 = Maharashtra |
| 3–12 | PAN of entity | AAAAA0000A |
| 13 | Entity number (same PAN, multiple registrations) | 1 |
| 14 | Default Z | Z |
| 15 | Checksum | 5 |
State codes (India)
- 01Jammu & Kashmir
- 02Himachal Pradesh
- 03Punjab
- 04Chandigarh
- 05Uttarakhand
- 06Haryana
- 07Delhi
- 08Rajasthan
- 09Uttar Pradesh
- 10Bihar
- 11Sikkim
- 12Arunachal Pradesh
- 13Nagaland
- 14Manipur
- 15Mizoram
- 16Tripura
- 17Meghalaya
- 18Assam
- 19West Bengal
- 20Jharkhand
- 21Odisha
- 22Chhattisgarh
- 23Madhya Pradesh
- 24Gujarat
- 26Dadra & Nagar Haveli and Daman & Diu
- 27Maharashtra
- 29Karnataka
- 30Goa
- 31Lakshadweep
- 32Kerala
- 33Tamil Nadu
- 34Puducherry
- 35Andaman & Nicobar Islands
- 36Telangana
- 37Andhra Pradesh
- 38Ladakh
FAQ
GSTIN validation FAQs
Does this tool check if a GSTIN is active on GST portal?+
No. PocketGST validates format and checksum offline only. To see active/cancelled registration status, use the official GST portal search.
What is the GSTIN format?+
15 characters: 2-digit state code + 10-character PAN + 1 entity digit + Z + 1 checksum character (e.g. 27AAAAA0000A1Z5).
Can I extract PAN from GSTIN?+
Yes. Characters 3–12 of a valid GSTIN are the PAN of the registered entity.
Why did my GSTIN fail checksum validation?+
A single wrong character (often O vs 0, or transposed digits) breaks the checksum. Re-type from the original registration certificate or invoice.