Tool comparison
HxD is a free hex and disk editor for Windows developed by Maël Hörz (mh-nexus). It opens files of virtually any size, plus raw disks and system RAM, and presents byte-level views with fast search, replace, export, and file comparison. In ECU tuning it is a staple for inspecting raw firmware reads, locating map or code regions by byte pattern, comparing an original dump against a modified one to confirm exactly which bytes changed, and applying manual patches. Built-in checksum and hash calculators, a data inspector, and fill/insert operations help verify edits and understand binary layout. Tuners reach for it alongside dedicated map editors whenever a change must be checked or performed by hand. It is lightweight, portable, and widely trusted in the community.
UltraEdit by IDM Computer Solutions is a veteran commercial text editor that also includes a full hex-editing mode, letting users switch between text and byte views of the same file. It handles very large files, offers powerful search-and-replace including regular expressions, column editing, and scripting/macros for automating repetitive changes. In tuning and firmware contexts it is used to view and edit binary reads in hex, search for byte or ASCII signatures such as ECU identifiers and software numbers, and script bulk edits across files. While not a dedicated reverse-engineering suite, its blend of robust text tooling and a capable hex mode makes it a practical everyday editor for people who work across scripts, logs, and binaries. It runs on Windows, macOS, and Linux.
HxD (Hex Editor / Reverse Engineering, mh-nexus (Maël Hörz)) and UltraEdit (Hex Editor / Reverse Engineering, IDM Computer Solutions) compete in the same space, so the choice comes down to coverage, workflow and price for your specific ECUs. Free Windows hex and disk editor used to inspect and patch ECU firmware dumps Text and hex editor with a column-mode hex view for binary files
Whichever you flash with, Softechpro Solutions auto-applies DPF/EGR/AdBlue/DTC-off modules and Stage patterns with automatic checksum correction across ~1,400 firmwares on Windows & macOS — the fast way to get the actual file edits done.
See SoftechproMore on HxD