Extract text from digital signature files (SIGN)
To convert SIGN signatures to another format, you need CryptoPro CSP or other Encoded software.
To convert other file formats to the "Digital Signature File" file type, you need software like CryptoPro CSP or a similar tool.
A .SIGN file is predominantly a detached digital signature created using cryptography standards like PKCS#7, CMS, OpenPGP, or Russian GOST algorithms. It is strictly used to mathematically verify that a specific digital document has not been altered or tampered with since the signature was applied. These files are typically generated and validated using specialized cryptographic software such as CryptoPro CSP or GnuPG. In rarer cases, they exist as plain-text XML Digital Signatures complying with W3C standards.
The main disadvantage of a .SIGN file is that it is typically "detached." This means the file only contains the cryptographic hash, public key, and certificate data, without holding the actual source document. Furthermore, proprietary signature formats require specific paid software like CryptoPro to validate and cannot be natively read by web browsers or standard operating systems. If you try to open a binary PKCS#7 .SIGN file in a text editor, you will only see unreadable characters.
Converting a .SIGN file usually means extracting the embedded public certificates into PEM, CER, or TXT formats for separate installation or analysis. If the signature is "enveloping" rather than "detached," the original file is embedded inside the signature; in this case, extracting the payload into the original format is the primary goal.
Because these files rely heavily on exact binary hashes and proprietary cryptographic modules, standard file conversion often breaks the mathematical proof. Often, only the original software can properly read or export the verified data. Our platform will inspect the file, extract any readable XML or plain-text certificate data, and detect if there is a supported embedded document ready for extraction.
Convert.Guru analyzes your SIGN file, detects the exact format, and lets you read the text inside.
Users also converted SIG, JPG, JPEG, ZIP, XMIND, PNG, FDCSS, SF, BISIGN, BLACK and PDF files.
If you want to convert SIGN file to PNG, JPG, BLACK or PDF, you can use CryptoPro CSP or similar software from the "Digital Signature Verification" category. In the File menu, look for Save As… or Export….
To convert files to SIGN, try CryptoPro CSP or another comparable tool in the "Digital Signature Verification" category.
The history of Convert.Guru began over 25 years ago in California with Tom Simondi’s file-format database. A former contributor to Space Shuttle development and a software pioneer of the 1980s, Simondi established a trusted resource for file type analysis that was even referenced by Microsoft Windows XP. Today, we use modern technology to process and convert thousands of file formats while continually improving our SIGN converter.