GST e-Invoice QR Code Decoder & Checker

What is inside. The QR text has three Base64URL parts separated by dots: a header (algorithm RS256 and a key identifier or thumbnail), a payload and a signature. The payload carries the invoice details in a "data" claim, with fields such as SellerGstin, BuyerGstin, DocNo, DocTyp (INV, CRN or DBN), DocDt (DD/MM/YYYY), TotInvVal, ItemCnt, MainHsnCode, Irn and IrnDt, and an issuer claim (iss). The decoder shows every field with its meaning, the header and the claims.

Format checks. GSTINs are checked for the 15-character pattern and the mod-36 check character, and the state code is shown; a buyer GSTIN can also be URP (unregistered person). The IRN must be a 64-character hexadecimal hash, the document type one of the known three, the date in DD/MM/YYYY form and the total value a number. A QR text that is not a three-part JWT, such as a plain UPI payment code, is refused with an explanation.

Signature. The token is signed with RS256 (RSA with SHA-256). No key is built into this tool, because the right key depends on the IRP and on the period and an outdated key would give a wrong answer. If you have the current public key or the certificate (PEM) from an official source, paste it and the decoder checks the signature with the browser\'s Web Crypto API and tells you whether it matches. A match shows the data was signed by the holder of that key. It does not show that the key is the official one, or that the invoice exists on the GST portal.

Where to verify. The details, including the IRN, can be looked up on the official e-invoice portal. This tool does not contact it, and no invoice data leaves the browser.

PDF (up to 50 MB, first 40 pages searched), PNG, JPEG and WebP images (up to 30 MB), or pasted text. The QR must contain a signed JWT in compact form. Optional signature check with an RSA public key or X.509 certificate in PEM form (never a private key).

1. Drop a PDF or an image of the e-invoice, or paste the long text from the QR code.
2. Read the invoice details, the token header and the format checks.
3. Optionally open "check the signature" and paste the public key or certificate you have, then decode again.
4. To confirm that an invoice is registered, use the official GST e-invoice portal.

• Reading the seller, number, date and value from the QR code of a purchase invoice
• Checking that the QR on a PDF carries the same GSTIN and total as the printed invoice
• Finding the IRN to look up an invoice on the portal
• Testing the QR output of billing software
• Understanding what a signed e-invoice QR contains

This tool does not guarantee that an invoice is valid in GSTN: it is not connected to it and cannot say whether the IRN is registered, active or cancelled. A decoded QR code with correct-looking fields can still belong to a forged or cancelled invoice. Different IRPs have used different keys over time, so signature checking needs a key you obtained yourself, and a match does not authenticate the key.

The field names and format checks follow the e-invoice schema as documented publicly by the system operators and their API providers; the description was checked on 6 October 2026 and can change. The GSTIN check character catches typing errors, not forged numbers.