Hexaunt

What Hexaunt Actually Is

Hexaunt is a hex editor for Windows. It lets you open binary files and edit raw bytes directly. Notepad++ with a hex plugin does something similar, but Hexaunt is built from the ground up for this purpose. It handles large files reasonably well, supports bookmarks, search patterns, and has a few other features that power users find useful. The interface is functional if you would describe it as utilitarian. It's not pretty. It hasn't been pretty since the mid-2000s. That's fine because that's not what you're using it for.

Where to Get Hexaunt

You can download it from the official site at hexaunt.com. The full version is shareware, which means it runs indefinitely but will nag you about purchasing a license after a certain period. The free version handles everything most people need. There's no point in looking for cracks or portable builds from third-party sites. You're editing sensitive binary data — why would you trust a modified copy? Open Hexaunt and go to File > Open. Navigate to your binary file. If the file is huge, say above a few hundred megabytes, give it a moment. The first load can take some time depending on your drive speed. SSD helps, obviously. Once it opens, the main window shows three panels. The top-left displays the file in hex bytes. The top-right shows the ASCII representation. The bottom panel is for search operations and other tools. Navigation is straightforward — arrow keys move through bytes one at a time, Page Up and Page Down jump by screenfuls.

Editing a byte is simple: position the cursor over it and type the new hex value. The editor updates in place. Save with Ctrl+S or File > Save. For read-only inspection, go to Settings and disable write access so you don't accidentally corrupt anything.

Search and Replace

The search feature is where this tool actually earns its keep. You can search for raw hex bytes, ASCII strings, or regular expressions. The hex search is most reliable — string-based searches can fail when encoding gets weird between UTF-8 and UTF-16 or when dealing with non-standard code pages. For large-scale replacements, use Edit > Replace. It works across the entire file or just the selected range. I always double-check the preview before hitting replace all. One wrong pattern in the right place and you've just destroyed a database file or a game asset. Learned that the hard way.

A Real Problem I Ran Into

Last year I was modifying a custom binary format for an embedded system — proprietary protocol, no documentation beyond a three-page spec sheet someone found in a GitHub repo. I needed to patch a magic number in the file header to bypass a version check on a dev board. Hexaunt opened the 4MB file fine, and I found the offset quickly with Ctrl+F. The problem came when I saved. The original file had a CRC checksum in the footer that recalculated based on the entire file contents. I changed one byte in the header and the CRC was now invalid. The board rejected the file immediately. What I should have done was look at the CRC algorithm first, calculate the correct new value, and patch both locations in one operation. Instead I spent about forty minutes reverse-engineering the checksum from test files before I figured out it was CRC-32 with a non-standard polynomial. I wrote a small Python script to compute the correct value and then went back into Hexaunt and patched the footer byte by byte. Total time wasted: an hour. Lesson learned — always understand the file format before you start poking at it.

Advanced Usage That People Miss

Bookmarking is underrated. Press F2 to set a bookmark at your current cursor position. The editor marks it with a red dot in the scroll bar area. You can jump between bookmarks with F3 and F4. If you're doing a lot of scattered edits across a large file, this saves you from using the find dialog repeatedly. The byte range selection is another thing most beginners overlook. Highlight a block of bytes and press Ctrl+I to fill it with incrementing values. Useful for generating test data or padding. Or use Ctrl+E to convert a selection to decimal, hex, or character representation without changing the underlying data. It's just a display option. The raw bytes stay the same. For disk-level work, Hexaunt can open raw sectors if you give it the right path like \\.\C: on Windows. This is how you edit boot records or partition tables. Be extremely careful here. One wrong keystroke and your OS won't boot. Keep a backup image first. Seriously.

Limitations You Should Know About

Hexaunt isn't ideal for every situation. It struggles with files above roughly 2GB on 32-bit systems. If you're working with massive disk images or memory dumps, you're better off with HxD or XVI32, which handle larger addresses more gracefully. The UI also doesn't support tabs, so opening multiple files means multiple windows. That's a minor annoyance until you're switching between four files at once and realizing you have four separate Hexaunt instances running. Another gap: no built-in disassembly. If you need to edit assembly code inside a binary, you'll want something like x32dbg or IDA Free alongside it. Hexaunt will show you the bytes, but it won't tell you what those bytes mean at the instruction level. The CRC and checksum features are basic. There's no auto-recalculation for common formats, no template system for known structures. You're on your own once the file gets complicated.

When to Use It and When to Move On

For quick binary edits, pattern searches, and general-purpose hex work on files under a couple gigabytes, Hexaunt is solid. It's fast, it doesn't crash often, and the learning curve is minimal. For anything involving disk sectors, memory dumps larger than 2GB, or files with complex embedded checksums, pair it with a proper disassembler or write a custom patching script instead of doing everything manually in the editor. The manual approach works until it doesn't, and then you've spent three hours figuring out why your patched firmware won't load.