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Free Tool · CGST Rules 2017 · Instant Checksum

GSTIN Validator

Verify any GSTIN's 15-character format, state code, embedded PAN, entity number, and checksum digit instantly — before raising an invoice or entering a new supplier.

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Reviewed by Harun Raaj, CA — ICAI Membership No. 238303  ·  Firm Reg. 19027S  ·  Updated July 2026

Enter GSTIN

Rule 9(1), CGST Rules 2017 · Section 25, CGST Act 20170/15

GSTIN Structure Reference

A GSTIN is always exactly 15 characters: SS PPPPPNNNNP E Z C

SS2-digit state/UT code (e.g. 27 = Maharashtra)
PPPPPNNNNP10-character PAN of the taxpayer
EEntity number (1–9, A–Z) — sequential for same PAN in a state
ZAlways the letter "Z" (default character)
CCheck digit computed by GSTN algorithm

Common State Codes

10Bihar
11Sikkim
12Arunachal Pradesh
13Nagaland
14Manipur
15Mizoram
16Tripura
17Meghalaya
18Assam
19West Bengal
20Jharkhand
21Odisha
22Chhattisgarh
23Madhya Pradesh
24Gujarat
25Daman & Diu (legacy)
26Dadra & Nagar Haveli
27Maharashtra
28Andhra Pradesh (legacy)
29Karnataka

Statutory Basis

GSTIN Format

GSTIN format is specified under Rule 9(1) of the CGST Rules, 2017 read with Section 25 of the CGST Act, 2017.

15-Character Structure

2-digit state code + 10-character PAN + 1-digit entity number + 'Z' + 1-character checksum (15 characters total).

State Codes

State codes are prescribed under the First Schedule to the CGST Act, 2017.

Checksum Algorithm

The checksum digit is computed using a modified Luhn algorithm prescribed by GSTN. This tool recomputes the check digit from the first 14 characters and validates it against the 15th character.

Frequently Asked Questions

What does a GSTIN look like and what does each part mean?+

A GSTIN is a 15-character alphanumeric code: first 2 digits = state code, next 10 = PAN of the entity, 13th digit = entity number for same PAN in same state, 14th = "Z" (default), 15th = check digit. Source: Rule 10, CGST Rules, 2017.

How do I check if a GSTIN is active or cancelled?+

You can verify GSTIN status on the official GST portal at gstin.gov.in/search-taxpayer. An active GSTIN means the taxpayer is registered and filing returns. A cancelled GSTIN means registration has been surrendered or cancelled by the department. Source: Section 29, CGST Act, 2017.

Can I claim ITC from a supplier with a cancelled GSTIN?+

No. ITC cannot be claimed from a supplier whose GSTIN is cancelled as of the date of supply. Always verify supplier GSTIN before making payment to protect ITC eligibility. Source: Section 16(2)(c), CGST Act, 2017.

What is the penalty for issuing invoices against a cancelled GSTIN?+

A taxpayer who continues to issue tax invoices after cancellation of registration is liable to a penalty under Section 122 of the CGST Act — up to ₹10,000 or the tax evaded, whichever is higher. Source: Section 122, CGST Act, 2017.

How many GSTINs can a business have?+

A business has one GSTIN per state per PAN. If operating in multiple states, separate registration is required in each state. A business may also apply for multiple GSTINs within the same state for different business verticals. Source: Section 25, CGST Act, 2017.

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