The application is distributed through Java Web Start. Typically all that's needed to install the basic version is to click on the install button below. The installation and use of the basic version are free. The program installed from this website is fully functional. However, the updates are automatic (that is just how Web Start works), and that is something you may or may not want. Also, you will not be able to add your own plug-ins. If you are interested in obtaining the source code or creating a local installation for which you can write your own plug-ins, please contact us.


Java 5 or later.


This software is provided by the copyright holders and contributors "as is" and Any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright owner or contributors be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage.
I agree to the above conditions

Zeptoscope Basic


Depending on the browser and system settings, the browser will either automatically start downloading the application or open a dialog window asking you what to do with the jnlp file: open or save. Choose 'Open'.

Once the download is complete, you should see a warning that the signature cannot be verified. Please ignore this warning for now. The application is currently signed with a test certificate, which was generated by the developer and not a certificate authority. The application requires full access in order to read the data files to be plotted.

If the browser is not configured to use a certain application to open jnlp files, then point it to Java Web Start: javaws on UNIX/Linux or javaws.exe on Windows.

To configure Netscape and Mozilla, click Edit -> Preferences -> Navigator -> Helper Applications -> New Type. Enter application/x-java-jnlp-file into MIME Type text box, Java Web Start into Description box and jnlp into Extension box. Check the 'Open it with:' button, click on the Choose button, and point the file browser to javaws in JRE installation directory. Opera browser is configured in a similar way: click Tools -> Preferences -> Advanced -> Downloads -> New. Enter application/x-java-jnlp-file into MIME type text box and jnlp into File extensions box. Check the 'Open with other application' button, click on the Choose button, and point the file browser to javaws.exe (e.g. C:\Program Files\Java\jre1.5.0_06\bin\javaws.exe).

It isn't clear how to configure Chrome to handle JNLP correctly. But when it saves the JNLP file, you should be able to double-click on it and proceed with the installation as described above.

After the application is installed, it will be updated automatically when you run it and a new version of the application is available (this is a standard Java Web Start feature). If after the update the application won't start and Web Start complains about some missing class file in a temporary directory, please try running the application again; if that does not help, uninstall it (e.g. on Windows though Control Panel -> Add/Remove Programs), then reinstall it from this page. User preferences will be saved.

Third-party open-source code

This project is not open-source, but it uses several excellent open-source libraries:

JFreeChart, released under the LGPL.
Copyright © 2005-2009 Object Refinery Limited
Original source code used in this project: jfreechart-1.0.5.zip
Modified source code used in this project: zeptoscope-jfreechart-mods.zip

JSci, released under the LGPL
JSci - A science API for Java
Copyright © 1996-2002 Mark Hale.
Copyright © 2002-2009 Mark Hale and contributors.

Commons Math, released under the Apache license
Copyright © 2003-2004 The Apache Software Foundation.

JAXB, released under the CDDL

Log4j, released under the Apache license
Copyright © 1999-2006, Apache Software Foundation.