GSTIN Validator: Check Any GST Number
A valid Indian GSTIN is exactly 15 characters: a 2-digit state code, the 10-character PAN of the business, a 1-digit entity number, the fixed letter Z, and a final checksum character. Paste any GST number above to verify its format and checksum instantly.
Valid GSTIN Format & Checksum Verified
State code, 10-character PAN structure, entity digit, fixed 'Z', and Mod-36 checksum all match official GST specs.
15-Character Anatomical Breakdown
27AAPFU0939F1ZV| Position | Characters | Meaning | Extracted Value |
|---|---|---|---|
| 1-2 | 27 | State / UT Jurisdiction Code | Maharashtra |
| 3-12 | AAPFU0939F | 10-Digit Entity / Business PAN | Permanent Account Number |
| 13 | 1 | Entity Registration Count | Registration #1 in Maharashtra |
| 14 | Z | Default Fixed Character | Always 'Z' |
| 15 | V | Cryptographic Check Digit | ✅ Mod-36 Verified |
This free tool verifies the 15-character structural format, state code eligibility, and mathematical Mod-36 checksum algorithm locally and offline. It does not query live taxpayer active/suspended status from the government database. To verify active GST registration, filing history, and legal business name, consult the official Services GST Portal (services.gst.gov.in).
Indian GSTIN Format & Structure Explained
Every business registered under the Goods and Services Tax Act in India is issued a unique 15-digit alphanumeric identifier known as a GSTIN (GST Identification Number). Each position in the 15-character string encodes specific legal and geographical information:
2-digit Indian Census state identifier (e.g. 27 for Maharashtra).
10-character Income Tax PAN of the business proprietor or company.
Registration number of business verticals under the same PAN in this state (1-9, A-Z).
Default placeholder character, currently fixed as 'Z' for all active taxpayers.
Cryptographic error detection digit generated via Luhn-style mod-36 formula.
Need to compute applicable tax breakdowns for an invoice? Use our free GST Calculator (CGST, SGST, IGST).
Complete Indian GST State Code List (01 to 38, 97, 99)
40 Official JurisdictionsBelow is the comprehensive list of 2-digit state and union territory jurisdiction codes defined under the Indian GST Act:
| State Code | State / Union Territory Name | Tax Jurisdiction Type |
|---|---|---|
| 01 | Jammu and Kashmir | State / UT |
| 02 | Himachal Pradesh | State / UT |
| 03 | Punjab | State / UT |
| 04 | Chandigarh | State / UT |
| 05 | Uttarakhand | State / UT |
| 06 | Haryana | State / UT |
| 07 | Delhi | State / UT |
| 08 | Rajasthan | State / UT |
| 09 | Uttar Pradesh | State / UT |
| 10 | Bihar | State / UT |
| 11 | Sikkim | State / UT |
| 12 | Arunachal Pradesh | State / UT |
| 13 | Nagaland | State / UT |
| 14 | Manipur | State / UT |
| 15 | Mizoram | State / UT |
| 16 | Tripura | State / UT |
| 17 | Meghalaya | State / UT |
| 18 | Assam | State / UT |
| 19 | West Bengal | State / UT |
| 20 | Jharkhand | State / UT |
| 21 | Odisha | State / UT |
| 22 | Chhattisgarh | State / UT |
| 23 | Madhya Pradesh | State / UT |
| 24 | Gujarat | State / UT |
| 25 | Daman and Diu | State / UT |
| 26 | Dadra and Nagar Haveli & Daman and Diu | State / UT |
| 27 | Maharashtra | State / UT |
| 28 | Andhra Pradesh (Old / Combined) | State / UT |
| 29 | Karnataka | State / UT |
| 30 | Goa | State / UT |
| 31 | Lakshadweep | State / UT |
| 32 | Kerala | State / UT |
| 33 | Tamil Nadu | State / UT |
| 34 | Puducherry | State / UT |
| 35 | Andaman and Nicobar Islands | State / UT |
| 36 | Telangana | State / UT |
| 37 | Andhra Pradesh (New) | State / UT |
| 38 | Ladakh | State / UT |
| 97 | Other Territory | Special Economic Zone / Other |
| 99 | Centre Jurisdiction | Central Government Jurisdiction |
Common Reasons a GSTIN Fails Validation
⚠️ OCR & Character Confusion
When reading paper bills or low-resolution receipt photos, optical recognition systems often confuse the letter O with number 0, letter I with number 1, letter S with number 5, or letter B with number 8.
⚠️ Invalid State Jurisdiction Code
Entering state codes outside the 01 to 38 range (such as 00, 39, 45, or 98) causes immediate failure as they do not correspond to any valid Indian state or union territory.
⚠️ Missing 14th 'Z' Character
Under statutory rules, the 14th character must always be the uppercase letter Z. If any other letter or number is present, the identifier is malformed.
⚠️ Checksum Digit Mismatch
Even if the format structure looks visually correct, if any single character in the PAN or state code is altered, the Mod-36 checksum algorithm produces a discrepancy, indicating a likely typo.
How to Verify if a GSTIN is Actually Registered & Active
While format and checksum verification confirm that a GST number is mathematically valid, confirming whether the taxpayer is actively registered, cancelled, or suspended requires querying the government database directly.
To check official taxpayer status and compliance:
- Visit the official Goods and Services Tax Portal (services.gst.gov.in/services/searchtp).
- Enter the 15-character GSTIN verified above.
- Inspect the legal trade name, principal place of business, GST filing frequency, and active registration certificate.
Frequently Asked Questions
Key questions on GSTIN structure, validation algorithms, and tax credit eligibility.
Q1.How many characters is a GSTIN?
A valid GSTIN (Goods and Services Tax Identification Number) in India is always exactly 15 alphanumeric characters long.
Q2.What is the format of a GSTIN?
A GSTIN follows a strict 15-digit structure: 2 digits for the State Code, 10 alphanumeric characters for the entity PAN, 1 digit representing the entity number for that PAN within the state, the fixed default letter "Z", and 1 final checksum character.
Q3.What does the first 2 digits of a GST number mean?
The first 2 digits represent the Indian State or Union Territory code according to the Indian Census 2011 standard. For example, 27 is Maharashtra, 29 is Karnataka, 07 is Delhi, 33 is Tamil Nadu, and 24 is Gujarat.
Q4.How is the GSTIN checksum calculated?
The 15th character of a GSTIN is calculated using a weighted Mod-36 checksum algorithm across the first 14 characters. Each character from the 36-symbol alphabet (0-9, A-Z) is assigned a numeric value, multiplied by alternating weights of 1 and 2, summed with quotients and remainders, and used to derive the final check symbol.
Q5.Can I check if a GSTIN is active?
Our tool validates the structural format, state code jurisdiction, and cryptographic Mod-36 checksum offline. To verify active taxpayer status, tax suspension, legal business name, or compliance history, use the official government portal at services.gst.gov.in.
Q6.Why does my GSTIN show as invalid?
A GSTIN will fail validation if it is not exactly 15 characters, has an unrecognised state code (outside 01 to 38, 97, 99), contains invalid PAN characters, does not have "Z" in the 14th position, or fails the mathematical check digit calculation due to a mistyped character (e.g. confusing letter "O" with number "0" or letter "I" with number "1").
Reading GSTINs off paper bills?
BillFetch extracts the vendor GSTIN, CGST, SGST and IGST from bill photos automatically and exports a GST-ready Excel. ₹50 flat, unlimited bills.