Welcome to Principia
Principia is a physics-based sandbox game. Build and play advanced contraptions, circuiting, minigames, puzzles, robot adventures and more. Open source, free and available for Windows, Linux, Android and more, download it today.
This site is the new community site for Principia. When you have installed Principia, enjoy the levels others have created, and register in order to upload your own levels and interact with the community.
Want to read more about Principia?
Also check out...
And the Official community site archive, an archive of old levels spanning from 2013 to 2018.
Apparatus player? Check out Principia for Apparatus Players on the Principia Wiki!
Featured levels
Latest news More
- 31 Dec 2025Principia in the web browser, and more...
- 6 Jul 2025Follow Principia on YouTube
- 14 Apr 2025New contest: Puzzling Puzzles
- 5 Apr 2025Principia 2025.04.05
- 22 Mar 2025Please help to test Principia
Top rated levels More
Latest custom levels More
Latest adventures More
Latest puzzles More
BobMonkeypimp2 commented on Satisfy: 15 hours ago
As an Englishman, your use of 'Z' irritates me 🤣randomguy123 commented on Dummy Gun: 1 day ago
Where do they go after being shot ....randomguy123 commented on Dummy Shotgun: 1 day ago
Am I tripping, or are these dummies...?randomguy123 commented on Boom enjin kar: 1 day ago
Poblem jenjin go kaput 💥Galaxium commented on Exp. rocket-auger v1.7 (Prot.): 2 days ago
Tends to lodge stuff between the emitters, causing the entire thing to have a seizure XPGlados commented on Tesla Principia!: 2 days ago
You can win just by touching any light to the right of the ball or the one underneathBobMonkeypimp2 commented on Dummy Gun: 3 days ago
If you set dummy durability to standard it becomes a dummy shotgun 😀Galaxium commented on lua digital experiment: 3 days ago
Yus