TRIDNet is the GUI version of TrID, probably more practical to use than the CLI version, especially for those not very familiar with the command line prompt.
Cost / License
- Free
- Proprietary
Alerts
- Discontinued
Platforms
- Windows

TrID is described as 'Allows to detect file type by recognition of binary signatures. Database with signatures can be downloaded from author site or trained by user with program named TrIDScan(see at author site)' and is an app. There are eight alternatives to TrID for Windows, Linux, Mac, Web-based and BSD. The best TrID alternative is TrIDNet, which is free. Other great apps like TrID are xdg-utils, file, Toolsley File Identifier and FileCHK.
TRIDNet is the GUI version of TrID, probably more practical to use than the CLI version, especially for those not very familiar with the command line prompt.

file is a standard Unix program for recognizing the type of data contained in a computer file using magic numbers.
Identify files based on the libmagic database in your browser. HTML5/JS port of the "file" tool. No downloads, no installation and no uploads!.

HexBrowser is a tool that identifies file types. It does not care about the file extension, but opens each file to look for signatures so it can determine the exact type of a file. It now recognizes more than 800 different file formats.

DROID (Digital Record and Object Identification) is a software tool developed by The National Archives to perform automated batch identification of file formats. Developed by its Digital Preservation Department as part of its broader digital preservation activities, DROID is...
JHOVE is a file format identification, validation and characterisation tool. It is implemented as a Java application and is usable on any Unix, Windows, or OS X platform with appropriate Java installation.