PhET Simulations

All simulations available at are open educational resources available under the Creative Commons Attribution license (CC-BY).

Permission is granted to freely use, share, or redistribute PhET sims under the CC-BY license. The following attribution is required:

PhET Interactive Simulations
University of Colorado Boulder

If your use includes redistribution of the simulations, please let us know with this form.

PhET-iO Simulations

PhET’s interoperable sims provide enhanced capabilities for interoperability with a wide variety of educational technology, including customization, streaming output data, and versatile API control. PhET-iO sims are a licensed product. Contact for more information.

Teaching Activities

A wide variety of teaching activities have been contributed by the PhET team and its user community, and are available for you to adapt and use in your classroom. If you require a CC-BY license, please check the specific activity to see if it is available under CC-BY.

PhET Name and Logo

The PhET name and logo are registered trademarks of The Regents of the University of Colorado.

Permission is granted to use the PhET name and PhET logo for attribution purposes. Use of the PhET name and/or PhET logo for promotional, marketing, or advertising purposes requires a separate license agreement. Contact for more information.

PhET Source Code

Most PhET simulation source code is available under an open source license – either MIT or GPL. PhET-iO source code is not openly licensed. Contact for alternate licensing options.

Full Text Agreements

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