Что такое формат файла MO?
.mo is a developer file used for storing a compiled binary translation catalog. .mo files are not human-readable - they are the machine-readable counterpart to a human-editable .po source file. Translators edit the .po file and compile it to .mo using the msgfmt command; the application then loads the .mo at runtime to display translated text. Modifying a .mo file directly will render it unusable.
Data access
.mo files are not encrypted or read-protected. Some hex editors can display the raw binary, but the correct way to recover human-readable strings is the msgunfmt command, which decompiles a .mo back into its .po source. Internally, a .mo starts with a four-byte magic number (0x950412DE little-endian), a revision word, and two offset tables pointing to original (msgid) and translated (msgstr) string arrays. An optional hash table enables fast runtime lookup.
Безопасность и защита
РИСК: LOWA .mo holds only translation strings and metadata - there is no executable code, so the file itself is harmless. The only practical caution: a malicious .mo placed in a theme/plugin could inject misleading interface text (e.g. altered links or instructions), so only use language files from the official theme/plugin source, not from unknown 'translation' downloads.
Детали формата
в двух словахПОЛНОЕ НАЗВАНИЕGNU gettext Machine Object (compiled translation catalog)также известен как Machine Object file, gettext MO file
РАЗРАБОТЧИКGNU Project / Free Software Foundation (GNU gettext)с 1995 (GNU gettext)
КАТЕГОРИЯФайлы разработчика
MIME-ТИПapplication/x-gettext-translation
ТИПBinary compiled translation catalog (hash-indexed string table)
СТАНДАРТОткрытый · без роялти
Это расширение также используется в…
- Autodesk Maya ASCII/object data - Some Maya pipelines and exporters use .mo for object data - unrelated to gettext.
- Modula-3 object file - Historic compiled object file for the Modula-3 language; the DB name reflects this rare meaning.
- Motorola / firmware object dumps - Occasionally seen for Motorola object/firmware blobs; niche and unrelated.
MAGIC BYTES · СИГНАТУРА ФАЙЛА
СМЕЩЕНИЕ
00010203
HEX
DE120495
ASCII
····
Magic number 0x950412de. If the file is little-endian the first four bytes are DE 12 04 95; big-endian MO files store it as 95 04 12 DE. The reader uses the byte order it detects to parse the rest of the header.
Программы, открывающие файлы MO
Windows2 apps
Poedit
Freemium File > Open the .mo to view it, or open the matching .po, translate, and save - Poedit writes the .mo automatically.
GNU gettext (msgunfmt / msgfmt)
Открытый код Run 'msgunfmt file.mo' to print the catalog as .po text, or 'msgfmt file.po -o file.mo' to compile. 
macOS2 apps
Poedit
Freemium File > Open the .mo to view it, or open the matching .po, translate, and save - Poedit writes the .mo automatically.
GNU gettext (Homebrew)
Открытый код brew install gettext, then 'msgunfmt file.mo' / 'msgfmt file.po -o file.mo'. 
Linux3 apps
GNU gettext
Открытый код Preinstalled on most distros: 'msgunfmt file.mo' to read it, 'msgfmt' to compile.
Poedit
Freemium File > Open the .mo to view it, or open the matching .po, translate, and save - Poedit writes the .mo automatically.
Web1 app
Poedit (web service for catalogs)
Freemium Use the desktop app; .mo files are best handled locally rather than via random online viewers. Технические подробности
глубокая спецификация| Format type | Binary compiled translation catalog (hash-indexed string table) |
| Magic number | 0x950412DE (little-endian: DE 12 04 95 at offset 0; big-endian files store 95 04 12 DE) |
| Byte order | Little-endian or big-endian; reader detects byte order from the magic number at parse time |
| MIME type | application/x-gettext-translation |
| String encoding | UTF-8 (most common); actual charset declared in the empty-msgid metadata entry |
| Metadata entry | Entry with empty msgid stores Project-Id-Version, Content-Type, charset, and Plural-Forms rules |
| Format revision | Revision 0 (both major and minor revision words are 0); revision 1 is defined but rarely deployed |
| Hash table | Optional fixed-size hash table embedded in the file body for O(1) string lookup at runtime |
| Compilation tool | msgfmt (GNU gettext) compiles .po → .mo |
| Decompilation tool | msgunfmt (GNU gettext) recovers a .po file from a .mo binary |
| Typical file size | 5 KB - 2 MB depending on the number of translated strings |
| Platform support | Linux, macOS, Windows, BSD - any OS running gettext-based software |
| Common deployment path | Installed as <domain>.mo inside an LC_MESSAGES directory under a locale tree (e.g. locale/fr/LC_MESSAGES/app.mo) |
| Выпущен | 1995 (GNU gettext) |
| Последняя версия | MO format revision 0 (still current); revision 1 defined but rarely used |
| Открыть стандартное | Да · без роялти |
| Спецификация | www.gnu.org |
Конвертации MO
Возможно
.MO .POРУКОВОДСТВО
Да, MO можно конвертировать в PO - самый быстрый способ одной командой: msgunfmt file.mo > file.po.
Как конвертировать
.MO .JSONРУКОВОДСТВО
Да - сначала декомпилируйте .mo в .po с помощью msgunfmt, затем конвертируйте .po в JSON с помощью po2json.
Как конвертировать
.MO .POTРУКОВОДСТВО
Да, с помощью двухэтапного конвейера GNU gettext: декомпилируйте MO в PO с помощью msgunfmt, затем удалите…
Как конвертировать
.MO .TXTРУКОВОДСТВО
Вы можете извлечь текст из файла MO с помощью msgunfmt из GNU gettext, который выводит каталог в…
Как конвертировать
Вопросы и ответы сообщества
спрошено пользователямиВопросов пока нет - станьте первым, кто спросит о файлах MO.
Часто задаваемые вопросы
What is a .mo file?
A compiled GNU gettext translation catalog - the binary version of a .po file that software loads to display its interface in another language. It's very common in WordPress, PHP and Linux apps.
How do I open or edit a .mo file?
Open it in Poedit, or decompile it with 'msgunfmt file.mo' to get readable .po text. Don't edit the .mo directly - edit the .po and recompile to .mo.
What's the difference between .po and .mo?
.po is the human-editable text catalog you translate; .mo is the compiled binary the program actually loads at runtime. You edit the .po and generate the .mo from it with msgfmt (or Poedit does both).
How do I create a .mo from a .po?
Run 'msgfmt file.po -o file.mo', or in Poedit just save the .po - it writes the matching .mo automatically.
Why is my WordPress translation not changing after I edited the .mo?
Edit the .po and regenerate the .mo (the app loads the .mo, not the .po). Also check that the filename matches the locale (e.g. plugin-fr_FR.mo) and that it's in the right /languages folder.
Can I read a .mo in Notepad?
Only partly - it's binary, so you'll see scrambled bytes with some readable string fragments. Use Poedit or 'msgunfmt' to read it properly.
Ссылки
1GNU gettext manual - The Format of MO Fileswww.gnu.org
2GNU gettext - official sitewww.gnu.org
