If you ever accidentally open an exe program file in a text editor such as Notepad you will be confronted with a mass of unintelligible garbage on your screen. Worse still if you write the exe file back to disk, the program file would almost certainly be corrupted and would not work. That's because text editors are designed only to work with text files which are files with extensions such as .txt, .bat, .prg and .html. To view and safely change binary files such as .exe, .com and .dll files you need a hex editor, sometimes called a binary editor. However, most average PC users have no need for such a program but techies and gamers find them indispensable.

There are some excellent free hex editors available that range from the small and simple editors to advanced products that are comparable to any commercial product. In total I looked at four products: HexEdit [1], Cygnus Free [2], Hxd [3], Hexplorer [4] HHD Free. Hex editors (like programming editors) are a software category where personal needs and preferences are so important that it is meaningless to pick a "best product". Instead I encourage all potential users to test several or all of the products and choose what suits them best. That of course doesn't stop me stating what I like.

For my needs, Hxd is a clear winner. Its first virtue is that it doesn't need installing. Second, it has a great interface. Third, it handles huge files without slowing down. Then add in unlimited undo, great searching and search/replace capabilities, full support for ANSI, DOS/IBM-ASCII and EBCDIC character plus a dozen other features and you can see why I like it. But it doesn't stop there. Hxd also works as a RAW disk editor and a full read/write RAM editor. Recently, binary file comparison has also been added to this product.

This power also makes it a dangerous tool in the hands of beginners. It may also give your security software apoplexy, but users skilled enough to use this product will understand this not a concern. Is it perfect? Of course not. To start, it lacks binary file comparison capability and the ability to extract text strings. A built in disassembler would also be nice. There are also a few bugs. However, what it offers is so impressive that it's hard to believe that this fine product is free.

[1] HexEdit
Website: http://www.physics.ohio-state.edu/~prewett/hexedit/
License: Freeware
Download file size: 147 KB
Windows Operating Systems Supported: 95/98/Me/NT/2000/XP/2003
Server/Vista
Non-Windows Operating Systems Supported: None
64 Bit Capable: No
Portable Version Available: No
Additional Software Required: None