A ja file extension is related to archive format used by Mozilla Firefox and other web browsers. A ja file contains various internal parts of web browser.

There are 2 other file types using
the JA file extension!

empty icon.ja - Japanese language translation

empty icon.ja - Trainz Railroad Simulator game data

Detailed description

Software that open ja file

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JA file extension - Mozilla archive

What is ja file? How to open ja files?

File type specification:

Archive and compressed file type icon Archive and compressed file type

The ja file extension is associated with archive file format used by some web browsers based on popular Firefox browser from Mozilla.

The ja file stores various internal parts of these web browsers. JA format is used to optimize web browser speed.

By default, the file is called omni.ja.

The default software associated to open ja file:

Firefox icon

Mozilla Corporation logoFirefox  Microsoft Windows software

Company or developer:
Mozilla Corporation

Firefox is very popular free open source web browser with many features. Firefox uses Gecko layout engine that implements most web standards including new HTML5.

Firefox supports tabbed browsing, private browsing, spell checking, incremental find, bookmarking etc. Other features can be added via extensions and add-ons, such as NoScript, Tab Mix Plus. FoxyTunes, Web Developer.

SeaMonkey icon

Mozilla Corporation logoSeaMonkey  Microsoft Windows software

Company or developer:
Mozilla Corporation

SeaMonkey is all-in-one internet application suite based on Firefox browser and Mozilla Application Suite.  SeaMonkey contains internet browser, email client, HTML editor, IRC chat and web development tools. It is also contains support for extensions and plug-ins.

Tor Browser icon

Tor Browser  Multiplatform software

Company or developer:
Tor Project

Tor Browser for Windows, Mac and Linux allows users to use Tor network. Tor Browser can run from USB flash drive, comes with a pre-configured web browser to protect user's anonymity, and is self-contained (portable).

Help how to open:

The ja format is similar to ZIP, you can rename *.ja file to *.zip and open it with some compression tools.

How to convert:

Probably cannot be converted to other formats.

List of recommended software applications associated to the .ja file extension

Recommended software programs are sorted by OS platform (Windows, macOS, Linux, iOS, Android etc.)
and possible program actions that can be done with the file: like open ja file, edit ja file, convert ja file, view ja file, play ja file etc. (if exist software for corresponding action in File-Extensions.org's database).

Unspecified and all other actions for computer programs working with ja file - Mozilla archive

Click on the software link(s) for more information. Suggested software applications use ja file type for internal purposes and/or also by different way than common edit or open ja file actions.

Microsoft Windows:

Main software associated with ja file by default:
Firefox small icon Firefox
SeaMonkey small icon SeaMonkey

Apple macOS / Mac OS X:


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