GNU Privacy Guard data
File type: Encoded and encrypted file
A sign file extension is used with GNU Privacy Guard (GnuPG). A sign file usually contains a detached digital signature for a separate file.
The signature is used to verify that the associated file came from the expected source and has not been changed.
File type category:
Encoded and encrypted file
Date updated: October 29, 2026
GNU Privacy Guard (GnuPG) is the GNU Project's software for encrypting and digitally signing data and communications. It supports Linux and other Unix-like systems, Microsoft Windows, and Apple macOS.
A sign file contains signature data created by GnuPG. It is normally stored separately from the file that was signed, and verification requires both the sign file and the corresponding signed data file. The signature does not contain the original file or an encryption key.
Use GNU Privacy Guard to verify or otherwise process a sign file. The corresponding signed file and, where required, the signer's public key must also be available.
GnuPG is available for Microsoft Windows, Apple macOS, and Linux/Unix. A sign file is not normally opened as a standalone document.
A digital signature cannot be meaningfully converted into the original file or into a general-purpose document format. Keep the sign file with the data file it authenticates.
GnuPG can create a new signature in another supported signature encoding when needed, but this produces a new signature rather than converting the signed content.
Software applications that can open sign files:
Microsoft Windows
Apple macOS / Mac OS X
Linux/Unix
Software apps that create sign files:
Microsoft Windows
Apple macOS / Mac OS X
Linux/Unix
Software applications that handle other tasks involving sign files:
Microsoft Windows
Apple macOS / Mac OS X
Linux/Unix
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