TheGSTCalculator.inGST tools for India
GSTIN Validator & Decoder

GST Number Validator & Decoder

Validate a GSTIN’s format, state/UT code, PAN, and checksum instantly. Use Bulk Validator to check many GSTINs and export results to CSV/JSON.

Format + checksum
Decode state + PAN
Bulk + CSV/JSON
Status: Verified 26 Jan 2026Last reviewed: 26 Jan 2026

GSTIN validator tool

Not legal advice • A checksum-valid GSTIN can still be inactive/cancelled — verify status on the official GST portal when it matters.
Loading validator…

Technical standards & who uses this tool

What we validate

The validator checks GSTIN structure and validates the checksum (last character) using a standard mod-36 approach. It also validates the PAN-like pattern embedded in GSTIN.

  • Structure rules: state code + PAN pattern + entity + “Z” + checksum
  • Mod-36 checksum validation (last character)
  • PAN format decoding (useful for quick screening)
Who uses this tool?
Accountants
Sanity-check GSTIN lists before data entry and reconciliations.
Business owners
Quick vendor invoice checks to catch typos and invalid GSTINs.
Developers
Test regex + checksum logic for forms and client-side validations.
Important
This tool checks structure + checksum. It does not confirm whether the GSTIN is active/cancelled. For legal status, verify on the official GST portal.
Privacy
GSTIN decoding and checksum validation run in your browser. We don’t need a server request for these checks. (External sites have their own policies.)

Deconstructing the 15-digit GSTIN

A GSTIN is not random — it’s a structured identifier. Here’s how to read it quickly.

01
State Code (Digits 1–2)
Represents the state/UT of registration (e.g., 27 = Maharashtra).
02
PAN (Digits 3–12)
10-character PAN embedded inside GSTIN.
03
Entity No. (Digit 13)
Sequence for multiple registrations under same PAN in a state.
04
Checksum (Digit 15)
Mathematically calculated character to detect typing errors.
STRUCTURE VISUALIZATION
27ABCDE1234F1Z5
Example GSTIN structure

What do the 15 digits in a GSTIN mean?

07State Code
AAAAA0000APAN Number
1Entity Code
Z 5Checksum

A GSTIN is a 15-digit unique identifier. It starts with a 2-digit State Code, followed by the 10-digit PAN of the business, a 1-digit Entity Code, the default letter 'Z', and a Checksum character.

How to validate a GSTIN

1
Paste the GSTIN
Enter a GSTIN (single) or paste a list in Bulk Validator.
2
Check validity
Confirm format + state code + checksum results.
3
Decode fields
Review state, PAN, entity number, and checksum details.
4
Verify status if needed
For active/cancelled status, verify on the official GST portal.
Need definitions? Visit GSTIN glossary.

This tool vs. GST portal

When to use this tool vs official GST portal search
FeatureThis ValidatorGST Portal
Checksum + structure validation✅ Yes (instant)✅ Not the main purpose
Decode state + PAN fields✅ Yes✅ Limited
Active/cancelled status❌ No✅ Yes
Bulk validation✅ Yes (CSV/JSON export)❌ Not convenient

GST state/UT codes list

Codes are used in the first 2 digits of GSTIN. Legacy codes may appear in older datasets—treat them as “verify”.
40 codesShow state/UT code table
Show +
GST state and UT codes used in GSTIN (first 2 digits)
CodeState / UTNotes
01
Jammu & Kashmir
STATE
02
Himachal Pradesh
STATE
03
Punjab
STATE
04
Chandigarh
UT
05
Uttarakhand
STATE
06
Haryana
STATE
07
Delhi
UT
08
Rajasthan
STATE
09
Uttar Pradesh
STATE
10
Bihar
STATE
11
Sikkim
STATE
12
Arunachal Pradesh
STATE
13
Nagaland
STATE
14
Manipur
STATE
15
Mizoram
STATE
16
Tripura
STATE
17
Meghalaya
STATE
18
Assam
STATE
19
West Bengal
STATE
20
Jharkhand
STATE
21
Odisha
STATE
22
Chhattisgarh
STATE
23
Madhya Pradesh
STATE
24
Gujarat
STATE
25
Daman & Diu (Old)
UT
LegacyCanonical: 26
Merged into code 26 (DNHDD).
26
Dadra & Nagar Haveli and Daman & Diu
UT
27
Maharashtra
STATE
28
Andhra Pradesh (Old)
STATE
LegacyCanonical: 37
Commonly treated as old AP; use 37 for current AP.
29
Karnataka
STATE
30
Goa
STATE
31
Lakshadweep
UT
32
Kerala
STATE
33
Tamil Nadu
STATE
34
Puducherry
UT
35
Andaman & Nicobar Islands
UT
36
Telangana
STATE
37
Andhra Pradesh
STATE
38
Ladakh
UT
97
Other Territory
OTHER
Special code sometimes used in legacy/internal mappings.
99
Centre Jurisdiction
OTHER
Special/internal mapping; not typical for standard GSTIN.
Tip: If you’re validating vendor lists for ITC, run a quick structure check here first, then reconcile with GSTR-2B Reconciler.

Examples

Example 1
Single GSTIN (invoice check)
  • Paste GSTIN from invoice
  • Confirm state code matches supplier state
  • Confirm checksum is valid (typo detection)
Example 2
Bulk GSTIN list (reconciliation prep)
  • Paste a list (space/comma/newline separated)
  • Export invalid ones to CSV for correction
  • Then proceed to ITC workflow / 2B matching

Frequently asked questions

What does this tool validate?

It checks the GSTIN’s format, verifies the state/UT code, and validates the checksum (last character). It also decodes the embedded PAN and shows an indicative PAN holder type.

Does “Valid” mean the GSTIN is active?

No. A checksum-valid GSTIN can still be inactive, cancelled, or suspended. For legal status, verify on the official GST portal.

Can I validate many GSTINs at once?

Yes. Switch to Bulk Validator, paste your list (line/space/comma-separated), and export results as CSV/JSON.

Is my GSTIN data sent to your server?

No. The validator runs in your browser for structure + checksum checks and does not require a backend call. (If you click external sites, their own policies apply.)

Sources & verification

This page focuses on structure-level validation (format/state/PAN/checksum). For compliance actions (filing, ITC, vendor onboarding), confirm legal status and registration details through official channels.

Verify status (official)
  • GST Portal search / taxpayer verification (official portal) — use “Search Taxpayer” on gst.gov.in
  • If you’re doing ITC work: cross-check vendor details with GSTR-2B / invoice data
What this tool does not do
  • Does not confirm active/cancelled/suspended status
  • Does not verify filing behavior or compliance score
  • Does not fetch data from government APIs
Last reviewed: 26 Jan 2026 • Update policy: we refresh state code data and validation rules when official guidance/utility formats change.

Next step

Valid GSTIN list ready?

If you’re validating vendor GSTINs for ITC workflows, the next step is to reconcile purchase data against GSTR-2B.

Open GSTR-2B Reconciler Compliance Hub
Not legal advice • Verify before filing
Disclaimer: This validator provides structure/checksum checks for guidance and does not confirm legal registration status.