How do I find out the file type without an extension? [duplicate]

After recovering my HDD, I ended up with a lot of files with no extension. Many of them are .bin files.

Is there any way to find out what file format they actually are?

Many of them have no information if I edit them with Notepad++ or Hex Editors.

Ahh, the dark arts of file identification.

I rather like trid for this. It identifies files (and renames them, if you choose), has a nice large database, and is totally independent of the file itself, so you have two approaches at your disposal.

There is also FileID which uses magicdb

http://www.optimasc.com/products/fileid/index.html

Explanation: FileID, TrID and File all work with magic numbers contained in the file which are supposed to be unique for each filetype, so all three programs are more or less equivalent. TrID is the most practical for windows users, while GNU/Linux ones simply use file.

You can try the file command for Windows

http://gnuwin32.sourceforge.net/packages/file.htm

Another tool that may come useful is ExifTool. Contrary to what the name may suggest, it can identify and extract medatada from more than your usual photos / images filetypes.