Verify a document
Every document RotorLab issues carries a document code. Enter it to see who issued it, when, and what was issued under it, then compare the file you were sent, byte for byte. No account, no upload.
Enter the code printed on the document. No account needed.
Check the file you hold
Choose the file you were sent (PDF, ZIP or text). It is hashed here in your browser and never uploaded; only its SHA-256 is sent. You can paste the hash instead: sha256sum file on Linux, shasum -a 256 file on a Mac, or certutil -hashfile file SHA256 on Windows.
What this check does
It confirms that a document with this code was issued through RotorLab, names the organization that issued it, and shows the SHA-256 of every file issued under the code. A file that matches one of them is, byte for byte, a file that was issued. A file that does not match has been changed since, even by one character, or was re-saved by another program; ask the sender for the file exactly as it was delivered.
What it does not do
This is not a digital signature and carries no legal signature status under ESIGN, eIDAS or any equivalent scheme. It does not say the records behind a document are true. It does not confirm who the organization is, or that it may use the name or logo shown; the organization supplies both. And it does not prove anything against RotorLab itself: the key is ours. It is a tamper-evidence and provenance check, nothing more. The organization that issued a document can see how many times its code was looked up, never by whom.