How to run Worlds

Worlds that can be run are usually indicated by a world image to click on, like these:

Blank Three.js World
383 runs ♦ 2 likes
Starter user
Simple World
725 runs ♦ 2 likes
Starter user

Sometimes the run is done by clicking a run button, like: and:

Try all of the above. They are working links.

A run opens a new tab or window

  • The run takes place on the client side in your browser.
  • A run opens a new tab or new window.

  • Camera control: Depending on the API, it may be possible for the user to control the camera in the run window. Try mouse drag (or touch drag on a touch screen) to move the camera. Try mouse scroll (or touch pinch on a touch screen) to zoom in and out.

  • To close the run window, click on the "Close" icon or on the normal close button or use some keyboard shortcut like Ctrl-W.
  • See keyboard shortcuts for closing tabs and windows on different operating systems.

Caution: A run is like clicking onto a random website

How much can we trust what we see in a run? The answer is not very much.

Our philosophy is to allow the upload of almost any JavaScript, subject to some basic checks. We do not want to put limits on the imagination of authors. Authors can write to the run window, redesign it and insert links into it. Essentially, World authors and Mind authors "own" the run window, as if it was their website.

Treat every run as if it is a new, unknown website that you have landed on after following a link on social media. Do not type any sensitive data into a run window. Follow any links in it with caution. Read any user comments, and check out who wrote it.

Please report misleading or malicious Worlds and Minds to We will delete such accounts. Trying to mislead users is against our terms and conditions.

We do not know of any drive-by exploit that can be implemented on this system just by uploading JS, given the other restrictions on the site, but it is possible that some exploit will emerge. We will continue to study this issue. Please report possible exploit ideas to

Note that:

  • Login pages are on a HTTPS server:
  • Runs are on a separate HTTP server:   where they cannot do any damage.

All user-submitted-content sites will have some problem with hackers, messers and vandals. Detecting and removing their work is a job that never ends. But hopefully, as on other user-submitted-content sites, it will be a manageable problem.

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