GST Number Checker
GST Number Checker: free, instant and private. The last character is a checksum computed from the other fourteen, so a single mistyped character is caught immediately.
How the GST Number Checker works
The GST Number Checker takes GSTIN and returns the answer instantly — no button to hunt for, no page reload. The last character is a checksum computed from the other fourteen, so a single mistyped character is caught immediately. The PAN inside the GSTIN also tells you which legal entity owns the registration.
Enter your own numbers to replace the example values; the result panel updates as you type. Everything runs in this single page, so nothing you enter leaves your device.
Formula used
GSTIN = state code + PAN + entity number + Z + checksum
| Symbol | Meaning |
|---|---|
| state code | first 2 digits — 27 Maharashtra, 29 Karnataka, 07 Delhi… |
| entity number | how many registrations exist under the same PAN |
The last character is a checksum computed from the other fourteen, so a single mistyped character is caught immediately. The PAN inside the GSTIN also tells you which legal entity owns the registration.
Inputs used: GSTIN.
Worked example
Take the default example — gstin of 29ABCDE1234F1ZW:
- Verdict: true
- Details: Karnataka · entity number 1 · PAN inside: ABCDE1234F
- state: Karnataka
- pan: ABCDE1234F
- entity: 1
Frequently asked questions
- What formula does the GST Number Checker use?
- It uses GSTIN = state code + PAN + entity number + Z + checksum, where state code is the first 2 digits — 27 Maharashtra, 29 Karnataka, 07 Delhi…; entity number is the how many registrations exist under the same PAN.
- Is the GST Number Checker free?
- Yes. There is no signup, no usage limit and no watermark — the calculator runs entirely in your browser.
- How do I read the result?
- The last character is a checksum computed from the other fourteen, so a single mistyped character is caught immediately. The PAN inside the GSTIN also tells you which legal entity owns the registration.
- Does the GST Number Checker store or send my data?
- No. Every calculation happens locally in the page, so the numbers you type are never uploaded or logged.
- Does it work on a phone and offline?
- Yes — the page is a single lightweight file that adapts to any screen size. Once it has loaded it keeps working without a network connection.