Tracker icon Tracker Online

Ver. 6.0.8

What is Tracker Online?

Tracker is a free video analysis and modeling tool from Open Source Physics (OSP) designed for use in physics education and hosted by the AAPT-ComPADRE Digital Library. Tracker has traditionally run only on the destop (Windows, Mac, Linux), but is now available online. Tracker Online is identical to Tracker on the desktop, it simply runs in JavaScript in a web browser rather than in Java on a desktop computer.

If you're new to Tracker, please see Help Getting Started for a step-by step beginner's guide or Getting Started with Tracker for a video tutorial. Additional information about Tracker is available on the Tracker website.

Using Tracker Online

You can reposition the Tracker window by dragging the title bar and resize the window by dragging the lower right hand corner.

There are several ways to open a Tracker Project or video in Tracker Online:

Supported Video Formats

Tracker Online can open the following types of videos:

Browser Support

Tracker Online is compatible with Chrome, Safari and Firefox browsers on desktop computers including Chromebooks. Compatibility with browsers on mobile devices is limited at this time.

Tracker Projects

A Tracker Project is a special Tracker zip file with extension .TRZ that contains everything needed to share the results of an analysis: Tracker tab files (.TRK), video files, and optional support documents in HTML or PDF format. Some Tracker Projects may use videos with older formats, such as MOV or AVI. These can be loaded into Tracker Online but they will not display the video. To fix this, you can convert older videos into a supported format using a third-party program, such as Cloud Convert. You can also convert your video clip into an image stack, such as Online Converter.

Bug Reporting and Testing

Use the Tracker Online Bug Report form to report bugs you discover in Tracker Online. Use the OSP Tracker Discussion forum for all other Tracker related questions or feedback. Please include the Tracker version number and build date shown in the Help | About Tracker drop down menu.

We welcome questions about how to use Tracker, suggestions for additional Tracker features, and bug reports related to the desktop version of Tracker.

Click on the links below to test Tracker Online on your computer.

With the links below you can download TRZ files or MP4 video clips to the desktop and then use File|Open File... or Video|Import... to open or import them into Tracker.


Tracker was written in Java by Douglas Brown at Cabrillo College using portions of the the Open Source Physics code library developed by Wolfgang Christian at Davidson College. Tracker was optimized and converted from Java to JavaScript by Robert M Hanson, Douglas Brown and Wolfgang Christian using the SwingJS system developed by Hanson and his students at St. Olaf College.