TrID is a utility designed to identify file types from their binary signatures. While there are similar utilities with hard coded rules, TriID has no such rules. Instead, it is extensible and can be trained to recognize new formats in a fast and automatic way.

TrID has many uses: identify what kind of file was sent to you via e-mail, aid in forensic analysis, support in file recovery, etc. TrID uses an XML-based database of definitions which describe recurring patterns for supported file types. The first 2KB of a file are examined for these patterns.

The database of definitions is constantly expanding; the more that are available, the more accurate an analysis of an unknown file can be. You can help! Use the program to both recognize unknown file types and develop new definitions that can be added to the library.

TrIDNet - File Identifier
TRIDNet is the GUI version of TrID. While it's probably more practical to use (especially for who isn't experienced with the command line), it even have a couple of intresting features.

M. Pontello