Q22

Free plan LinuxWindows

What Q22 is

Q22 is a free, open-source binary file editor for Linux and Windows, described as the successor to Catch22 HexEdit for Windows. It opens and edits binary files, including large files, with cut, copy, paste, insert, delete, undo, and redo. Data can be shown as hexadecimal, decimal, octal, binary, or text, and bytes can be grouped into 8-bit, 16-bit, 32-bit, or 64-bit values.

Structure View works with PE and ELF files, letting users expand headers, sections, imports, exports, and symbols. It also accepts custom .strata definitions in Strata. The disassembler supports x86 in 32-bit and 64-bit modes, ARM, ARM Thumb, and AArch64, and detects PE and ELF entrypoints automatically. Users can bookmark and highlight positions in the hex display, and bookmark state is saved for future use.

Clipboard, import, and export formats include hex, ASCII or text, raw data, Base64, UUEncode, Intel HEX, Motorola S-records, HTML, C++, C, and assembler-style data. Panels provide file properties, checksum calculation, and string extraction. Q22 offers light, dark, and system themes, built-in and custom palettes, configurable preferences, a custom titlebar, and docked panels. Its window chrome supports Windows, KDE/KWin, and GNOME/Mutter.

Who it suits

Q22 suits people who need to inspect or edit binary files on Linux or Windows, including users working with PE or ELF structures and supported processor instruction sets. Its multiple data views, structure tools, and import and export formats also fit workflows that use varied representations of binary data.

What it does well

Free and licensed under GPL-3.0-or-later.
Edits large binary files with undo and redo.
Displays data in five number or text formats.
Structure View supports PE and ELF files.
Disassembler covers x86, ARM, ARM Thumb, and AArch64.
Bookmark positions are saved for future use.

What to know first

Linux availability is listed as Fedora currently.
The listed platforms are Linux and Windows.

Plans

Plan	Billed and limits	Price
Q22	GPL-3.0-or-later · Linux (Fedora currently) · Windows	Free

As catch22.net lists them, read 5 Oct 2026. The maker's own page has the final word.

Getting started

Visit the Q22 project website.
Choose the Linux or Windows version for your platform.
Install or run Q22 on your system.
Open a binary file to inspect or edit it.

Verdict

Choose Q22 if you need a free binary editor with PE and ELF structure views, disassembly, and several data formats on Linux or Windows. Check the platform details if you need a Linux distribution other than Fedora, which is the one currently named.

Questions

Is Q22 free?

Yes. The Q22 plan is listed as free, and the software is open source under GPL-3.0-or-later.

Which platforms does Q22 support?

Q22 is listed for Linux and Windows. Linux is currently listed as Fedora.

What file structures can Structure View handle?

It supports PE and ELF files and can expand their headers, sections, imports, exports, and symbols. Custom .strata definitions in Strata are also supported.

Which processor architectures does the disassembler support?

It supports x86 64-bit, x86 32-bit, ARM, ARM Thumb, and AArch64.

Who makes Q22?

The maker's About page identifies James Brown and says he lives in Hampshire, UK.

What license does Q22 use?

Q22 is licensed under GPL-3.0-or-later.

Facts from Q22's own pages

Bookmarks: Users can bookmark and highlight positions in the hex display, and bookmark state is saved for future use. · catch22.net, 5 Oct 2026
Customization: Q22 offers light, dark and system themes, built-in and custom palettes, configurable preferences, a custom titlebar and docked panels. · catch22.net, 5 Oct 2026
Data views: It displays data as hexadecimal, decimal, octal, binary or text, and groups bytes as 8-bit, 16-bit, 32-bit or 64-bit values. · catch22.net, 5 Oct 2026
Disassembly: The disassembler supports x86 64-bit, x86 32-bit, ARM, ARM Thumb and AArch64, and detects PE and ELF entrypoints automatically. · catch22.net, 5 Oct 2026
Editing: It can open and edit binary files, including large files, with cut, copy, paste, insert, delete, undo and redo. · catch22.net, 5 Oct 2026
Import and export: Supported clipboard, import and export formats include hex, ASCII/text, raw data, Base64, UUEncode, Intel HEX, Motorola S-records, HTML, C++, C and assembler-style data. · catch22.net, 5 Oct 2026
License: Q22 is licensed under GPL-3.0-or-later. · catch22.net, 5 Oct 2026
Maker: The maker's About page identifies James Brown and says he lives in Hampshire, UK; it does not state a founding date. · catch22.net, 5 Oct 2026
Other tools: The interface includes file properties, checksum calculation and string extraction panels. · catch22.net, 5 Oct 2026
Platforms: The page lists Linux (Fedora currently) and Windows as supported platforms and says more are to come. · catch22.net, 5 Oct 2026
Purpose: Q22 is a cross-platform binary file editor and the successor to Catch22 HexEdit for Windows. · catch22.net, 5 Oct 2026
Release: The GitHub releases page lists q22 3.3.0, dated 2026-09-12. · github.com, 5 Oct 2026
Structure View: Structure View supports PE and ELF files, can expand their headers, sections, imports, exports and symbols, and accepts custom .strata definitions in Strata. · catch22.net, 5 Oct 2026
Window integration: Its platform-specific window chrome supports Windows, KDE/KWin and GNOME/Mutter. · catch22.net, 5 Oct 2026

Where Q22 stands on Freedom251

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