Verified · 29 Sept 2026
GST Number Checker – GSTIN Format & State Validator
Check whether a GSTIN is correctly formed, verify its checksum, and see the state and PAN it belongs to.
✓ Verified against official notifications · 29 Sept 2026 · How we verify →
15 characters: state code (2) · PAN (10) · entity number (1) · Z · checksum (1).
Valid GSTIN format and checksum
State
Maharashtra
Code 27
PAN
AAPFU0939F
Entity no. 1
Live registration
Live lookup sends this GSTIN to our verification provider. Paid plans.
FY 2026-27 · GST 2.0 slabs (5% / 18% / 40%) from 22 Sept 2025 · interest on net cash only (s.50 proviso, CBIC Circular 26/2022)Verify on gst.gov.in →Share on WhatsApp
For estimation only. This calculator applies the rules as we understand them on 29 Sept 2026. It is not legal or tax advice. Verify with the official notification or consult a Chartered Accountant / labour-law professional before filing or changing payroll.
Did this tool give you the right answer?
What each character means
Take the sample GSTIN 27AAPFU0939F1ZV:
| Position | Value | Meaning |
|---|---|---|
| 1–2 | 27 | State code: Maharashtra |
| 3–12 | AAPFU0939F | PAN of the holder |
| 6 (4th letter of the PAN) | F | Holder type: F is a firm, C a company, P an individual, H an HUF, T a trust |
| 13 | 1 | First registration under this PAN in this state. Goes 1–9, then A–Z |
| 14 | Z | Fixed as Z for regular registrations |
| 15 | V | Checksum calculated from the first 14 characters |
How the checksum catches typos
Each of the first 14 characters is turned into a number from 0 to 35, with every second one doubled. The digits of those results, in base 36, are added up, and the 15th character is whatever brings the total to a multiple of 36. Change any single character and the checksum no longer fits. Change the last letter of the sample to X, making 27AAPFU0939F1ZX, and the validator rejects it.
That catches almost every single-character typo and most swapped pairs. It cannot catch a GSTIN that is correctly formed but belongs to someone else.
Valid is not the same as active
A GSTIN can pass the checksum and still be cancelled, suspended or fake. Before you pay a new supplier or book credit on their invoice, look it up with Search Taxpayer on the GST portal. Check that the legal name matches the invoice, the status is Active, and the returns are being filed. Credit on an invoice from a cancelled GSTIN will not appear in your GSTR-2B.
Quick checks on an invoice
- The PAN inside the GSTIN should match the supplier's PAN on their other documents.
- The state code should match the state in the supplier's address. A mismatch means the wrong branch GSTIN or a wrong place of supply.
- For your own customers, a wrong GSTIN on an e-invoice is rejected by the IRP. See the portal error lookup for the exact error.
Official sources
Frequently asked questions
What does a GSTIN contain?
A 2-digit state code, the 10-character PAN, an entity number, the letter Z, and a checksum character.
Does a valid checksum mean the GSTIN is active?
No — it only means it is correctly formed. Use Search Taxpayer on the GST portal to confirm its status.