DataWorkhop!

HxD is a carefully designed and fast hex editor which, additionally to raw disk editing and modifying of main memory (RAM), handles files of any size.

wxHexEditor is an open source cross-platform disk/sector/file hex editor written in C++ with a wxWidgets-based user interface.

WinHex is a hexadecimal editor capable of opening disks, sectors, files (native support for FAT, NTFS, Ext2/3, ReiserFS, Reiser4, UFS, CDFS, UDF) and physical memory (RAM). It can read, write and extract data for a further forensic analysis.

A fast and clever open source HEX editor for Mac OS X.

HexEdit is a hexadecimal file editor for Microsoft Windows. HexEdit allows the user to view and edit any type of file, no matter what format it is saved in.

FileAlyzer is a tool to analyze files, allows a basic analysis of files (showing file properties and file contents in hex dump form) and is able to interpret common file contents like resources structures (like text, graphics, HTML, media and PE).

Bless is a high quality, full featured hex editor. It is written in mono/Gtk# and its primary platform is GNU/Linux. However it should be able to run without problems on every platform that mono and Gtk# run on.

The Hex Workshop Hex Editor by BreakPoint Software is a complete set of hexadecimal development tools for Microsoft Windows 2000 and later. Hex Workshop combines advanced binary editing and data interpretation with the ease and flexibility of a modern word processor. With the Hex Workshop, you can edit, cut, copy, paste, insert, fill and delete binary data. You can also work with data in its native structure and data types using our integrated structure view and smart bookmarks. Data editing is quick and easy with our extensive features that allow you to: jump to file or sector location, find or replace data, perform arithmetic and logical operations, binary compare files, generate checksums and digests, view character distributions and export data to RTF or HTML for publishing. »

A hexadecimal low level disk editor with extensive templates for NTFS, FAT and exFAT partitions

Hiew (short for Hackers view) is a popular console hex editor for DOS and Windows written by Eugene Suslikov (sen). Amongst its feature set is its ability to view files in text, hex and disassembly mode. The program is particularly useful for editing executable files such as COFF, PE or ELF executable files.

Open Source powerful and flexible Hex-Editor, with multiple colour-schemes that allow easy visual indication of byte-magnitude.