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Download and Install


You are free to copy, distribute and transmit Easy Java Simulations for non-commercial purposes.
Please see the EJS license for details.

Download (for Windows, MacOSX, or Linux/Unix)

Reader App for tablets and smartphones

The Reader App is available in the GooglePlay (for Android) and the App Store (for iOS). Search for EjsS.


Current version

    • Version 5.2 improves the generation of ePubs and includes a new “Export as MacOSX widget” option in the Javascript flavour of EjsS. (And several bug fixes.)
    • Starting release 151018, the Javascript preview can be displayed using your favourite Web browser (instead of the slow, and sometimes problematic Emulator).
    • Changes in release 151201:
      • Corrects a minor problem in Java3D (missing textures caused an exception, now they produce a console warning)
      • Makes the Java libraries Java 1.6 compatible (for Mac users wanting to use Java3D). This allows creating truly Java 1.6 executable jar files.
      • Adds Java model elements for Robotics.


  • IMPORTANT: EjsS 5.X Requires Java Runtime Environment (JRE) 1.7 or later.
    • Note for MacOSX users: Java 1.7 and Java3D seem to be incompatible! (If you fix this problem on a Mac, please let me know.)


The file name ending _yymmdd indicates year, month, day of built.

Previous versions

    • Version 5.1 included Model elements for Javascript and audio and video HTML View elements. (And several bug fixes.)
    • Version 5.0 is a new major release of EjsS, featuring the possibility to create HTML+Javascript simulations that run on tablets and smart phones.
    • Includes a completely new family of ODE solvers, both in Java and Javascript. These solvers support events, discontinuities of the ODE, and state-dependent (albeit non-vanishing) delays.
      • Note: The Radau5 solver does not support discontinuities or delays.
      • Note 2: Because the solvers implement the numerics algorithms differently, the precise numbers you can get may differ slightly (of th eorder of magnitude of the tolerances prescribed). But the qualitative behaviou should be the same. If not, then please report it as a potential bug.
    • Backwards compatibility notes:
      • The new ODE solver library does not include the experimental QSS solver.
      • Except for this, the solvers and previous EJS files are backwards compatible.
      • Some view element properties have been deprecated (such as “Initial Value” for Slider and NumberField).


Version 4.3.7 is a minor, but important update with some bug fixes and the upgrade to Apache Commons Math library version 3.0. Also has new Model Elements.
Here is a mirror link for the latest official release in the ComPadre digital library, which can be faster for American users. There may be a difference of days in the versions (specially when I fix bugs), but all official releases are mirrored quickly.

Requires Java Runtime Environment (JRE) 1.5 or later.

Version 4.3.6 is a minor update with some bug fixes, interactive axes scaling in plotting panels, and Points elements with different colors and line widths.
EJS version 4.3.5 introduced support for video. (Xuggle required, install Xuggle using Tracker installer.)
EJS version 4.3.4 introduced new model elements for parallel programming.
EJS version 4.3.3 introduced support for Delay Differential Equations.
EJS version 4.3.2 introduced Model Elements, a palette of ready to use elements which provide access to library functions.
This is the last release of EJS version 4.3.1  (except for possible bug fixes).
EJS 4.3.1 introduced a new translation facility that helps internationalize existing simulations. See the video about translation in the Webcasts page of this wiki.
This is the last release of EJS 4.3.0 (except for possible bug fixes).
EJS version 4.3.0 introduced a complete new 3D framework, more powerful and with a better support for Java 3D. This release also introduces a utility to check for updates either automatically or manually.
This is the last release of EJS 4.2 (except for possible bug fixes).
EJS version 4.2 introduced new solvers and more types of events. EJS version 4.2 update 7 (4.2.7) fixes some problems in 4.2 with non-standard characters by introducing a new file format, with the extension “.ejs”, to save simulations. This format supports glyphs (non English characters) in a cross platform independent way. The ‘old’ format “.xml” is still supported.
This is the last release of EJS 4.1 (except for possible bug fixes).
This version of EJS 3.47 is the last release (so far) with support of connections to Matlab/Simulink (Windows only).


  • Unzip the distribution file. This will create a new folder, e.g. EJS_4.2.
  • Start EJS with the file EjsConsole.jar.

You can also read more detailed installation instructions.
Not sure what to download? Read download instructions.

Source code

Easy Java Simulations is Open Source under a GNU GPL license. If you are interested, you can download the complete source code and data.


You are free to copy, distribute and transmit Easy Java Simulations for non-commercial purposes.
Please see the EJS license for details.

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Page last modified on December 01, 2015, at 09:29 PM