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.


4 Answers 4


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.

  • 1
    learned something better while trying to help. wonderful and thank you!
    – johnshen64
    Jun 11, 2012 at 14:37
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    Its a really neat bit of software. I've just been waiting for a chance to use it properly ;p
    – Journeyman Geek
    Jun 11, 2012 at 14:46
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    For amateur users like me ( cause took me some time to figure out ) , there is a window version ( I mean visual one ) TrIDNet which require TrIDLib also , again Thanks man all of my files are healthy , also after searching i figured out how to use batch mode and replace all extensions to right ones , Thank you
    – echolab
    Jun 11, 2012 at 21:08
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    A bit late but, actually, TrIDNet (a .NET application) don't require TrIDLib (a Win32 DLL).
    – Mark0
    Jan 9, 2013 at 14:04
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    Awesome tool. I just used it to figure out that an email attachment I was sent to decipher was a .gz file, not a .tar file as its extension showed. Once I unzipped the .gz file I actually got a .tar file, so it was really originally a .tar.gz file. I then extracted the .tar file to find a SQL script with a .sql extension and a JSON file with no extension. Except that the SQL script wasn't actually a SQL script, but another .gz file containing the actual .sql file. Ha ha. May 20, 2016 at 7:16

There is also FileID which uses magicdb


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


  • it shows this , what that mean data , what kind of data C:\Program Files (x86)\GnuWin32\bin>file file01929.bin file01929.bin; data , is there any more advance tool ?
    – echolab
    Jun 11, 2012 at 11:49
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    "Data" means it makes no sense to the file command. Jun 11, 2012 at 12:02
  • Try mark0.net/onlinetrid.html Jul 6, 2022 at 3:40

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.

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