Software Requirements & Installation


To use OmegaT+ it is necessary to have a Java Runtime Environment (JRE) installed. Free downloads of JRE are available for different operating systems.

The minimum version of JRE guaranteed to function properly with this version of OmegaT+ is Java 6.

Information for Java support on specific operating systems is given in the following sections.


Most Linux distributions come with some type of JRE by default. Many of these default installations will not have a version with proper Java (Swing) support to run OmegaT+. Notably, most Ubuntu distributions and its derivatives (Kubuntu, Xubuntu, etc.) will not work properly unless an Oracle JRE is installed. Other distributions may have the same requirement.

Oracle Java (formerly Sun Java): fully supported with versions for Linux (32/64 bit) and widely available.

OpenJDK: near to full support with (almost) proper Swing functionality. Numbers of Linux distibutions may include this version, or a derivative of it, in their package offerings (e.g., Fedora, Mandriva, RedHat, Ubuntu, etc.).

Blackdown Java: this does not work since there is no stable 1.5 or greater version available, and the project ceased operation in 2007.

GCJ (GNU Compiler for Java) and Classpath implementations: these do not work with OmegaT+ due to lack of sufficient Swing functionality.

Other vendors may also provide Linux versions, but compatibility is indeterminate. If you do try a JRE from another source other than Oracle, please provide feedback to this project about any success or problems with it so that future users may benefit.

Mac (Apple Macintosh)

OS X: comes with a JRE installed by default, but a particular version may require upgrade, if that is at all possible. Please check with Apple and use the Software Update feature on the Mac to get the latest Java version.

Java 6 is available for Snow Leopard (10.6, 32/64-bit) and Leopard (10.5, 64-bit) currently. Java 5 (32/64-bit) is available from Tiger (10.4) forward, for which there is a separate package that can be used for installation (i.e., OmegaT+1.0.M3.1-Tiger.dmg). There is no support for Panther (10.3) and below, due to the unavailability of Java 5 before OS X 10.4 (Tiger).

The use of Java 6 (or Java 5) might not be set as the default and will need to be changed in that case by using the Java Preferences utility in Finder.

Other: there is no version of Java 5 or greater available.


Windows 7, Vista, XP, 2003 Server, 2000: full support from Oracle with the latest JRE. Other vendors may also supply JRE that work, compatibility is indeterminate.

Windows ME, 98: may work, but erroneous operations may result in some circumstances. If you are using a version that old, you are better off switching to Linux, which will run faster on the same hardware and can be obtained for free.

Other: not supported. There is no JRE that has the required functionality for proper operation.


BSD (FreeBSD, NetBSD, OpenBSD, etc.): indeterminate at present. Please report to the project any success so that the relevant information can be added. There is a FreeBSD port of Oracle Java (5/6 ?).

IBM AIX: supported by versions from IBM (AIX creators).

Solaris, OpenSolaris, and derivatives: fully supported by versions from Oracle.


It is not currently known if OmegaT+ can run on other operating systems, with suitable JRE. Please report to the project any success running on other systems so the information can be included here to help future users.

Java Providers

Java Installation

Please follow the installation instructions that come with the JRE given by the particular vendor. It is also a good idea to test out your Java installation to ensure that it works before installing OmegaT+. An implementation may come with utility applications that can be run.

Mac OS X users: Java is already installed, but upgrade to a newer stable Java 6 series version is necessary if you don’t have it already (if your system can be upgraded to it). Go to the Apple website to get more details about upgrading Java (you will need to upgrade the operating system if it is too old, hardware must meets the requirements for a newer version of OS X).

OmegaT+ Installation

The following sections contain information about installation for the package formats available. Note that not all packages can be opened or installed on all platforms and that some of the previously available package formats have been dropped (e.g., .tar.gz, and .tar.bz2), as well as a few new ones becoming available (i.e., .dmg, .rpm). At least one of the package types given will open on all the popular platforms or with freely available tools.


7-Zip(.7z): decompress the archive contents into a directory of your choice. Set your path variable to include the installation path in order to easily start OmegaT+ from any directory when using a shell. Depending upon the window system manager in use, you should also be able to create a desktop icon, desktop menu item, or task bar icon to quickly launch the program. Check your specific window manager’s documentation on how to do this.

A 7-Zip application is now included in a number of distributions by default (e.g., Mandriva). Try to open the package with your favorite archiver application (e.g., it works in KDE's Ark under Mandriva), if it does not work then you will need to install the 7-Zip port (P7ZIP) package, if your distribution has one, or install by getting the application directly from the project--this may require compilation:

RPM(.rpm): on Linux systems that support RPM installation, become root and simply enter

# rpm -Uvh OmegaT+<-xxxx>.rpm

(for verbose output), or just

# rpm -U OmegaT+<-xxxx>.rpm

to install in the usual manner (where <-xxxx> is the version number part of the filename; not literally "-xxxx"). You need to have system administrator privileges to do this. Ask your system administrator about installation if you are not able to install by yourself.

Mac OS X

.dmg: the usual OS X disk image format should open/mount automatically when downloaded or can be clicked to open. The contained OmegaT+.app can be run directly from the mounted image or be moved to a location of your choice.

7-Zip: Mac OS X can open these archives for installation with free tools that are now available. Just decompress the archive into the folder of your choice. It is possible, but not completely necessary, to set your path variable to include the installation path in order to easily start OmegaT+. This will only apply when working from a shell.

7-Zip applications for OS X:


7-Zip and Zip Packages: these packages can be opened on Windows, given the right decompression program is installed. To use 7-Zip try an application from one of the following (note: the 7-Zip application can also open Zip files):

Other Software

Some or all of the following software is needed to use OmegaT+ effectively.


When translating and working with translation memory formats it may be necessary to alter the level at which the original and translated text is broken up into pieces or text units. These pieces are referred to as the segments and the act of breaking up the text is known as segmentation. Once segmented, with appropriate software it is possible to change the segmentation so that the translation memory document can be used in other situations with other software.


Bitext is text from mutually translated text that is aligned into related segments. The bitext may be processed further so that it is ready for use in other programs.

One free open source application that can be used is bitext2tmx (B2T), that when given original and translated text documents attempts to aligned the contents as best it can into the related segments. The user then verifies and corrects mistakes in the alignment, followed by export of the aligned text into TMX or other format which can be used in other applications, like OmegaT+.

This is a great addition to your toolbox because any old translations you have in computer document form from past work can be converted into TMX for use in OmegaT+. Instead of having to laboriously type everything into OmegaT+ again, you just review and adjust the alignments provided by B2T and save it to a TMX, ready for use. It may take a while to do this if you have large documents, but it will definitely take only a small fraction of the time compared to re-typing every translation.

Office Suite

To use OmegaT+ with documents in certain file formats a compatible office suite is necessary. This will be needed to either read/write or to convert from other formats. At present, OmegaT+ is only capable of reading and writing OpenOffice.org(OOo) or OpenDocument(ODF) office suite documents, with preliminary support for OOXML (the XML version of MS Office formats). These include wordprocessor, spreadsheet, presentation, and so forth. OmegaT+ does not natively support regular Microsoft Office documents(e.g., .doc, .ppt, .xls), but they can be converted to OOo or ODF given conversion software or an office suite that can handled them. This is usually what is done and in practice it does not cause many problems.

Note: in future versions of MS Office, OpenDocument will be 100% supported. Thus, clients using MS Office will be able to send/receive documents for translation by exporting/importing to/from ODF first. Translators will be able to use OpenOffice.org with full confidence that there will be no chance of loss of formatting, layout, or data (we hope!). Just get your clients to cooperate and use ODF, good luck.

Here are a few applications that can be used to a greater or lesser extent:

Text Editor

If you are translating from plain text files, any text editor set to the appropriate encoding can be used.

Some examples: Emacs, vim, kate, wordpad, kwrite, kedit, and so on.

Web Browser

Working on localization of a website? Then you will need a web browser, like you don't use one already. You can also use the browser to read the OmegaT+ documentation that comes with the installation.

Disclaimer & License

All trademarks contained herein are the property of their repsective ownwers. This documentation is released under the OPL license. OmegaT+ is released under GPL license. See Issues page for other details.

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