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Submitted by Xenoveritas on

Play Tetris in Mozilla! MozTris is an implementation of Tetris using Javascript, HTML 4.0, CSS, and the Mozilla DOM. It also makes use of the PNG format for various images. If you use Opera, you can also play MozTris!

This will not work in Internet Explorer.

New in 1.2.1

The field size has been increased to a standard 10x20 blocks, which forced the background graphics and block graphics to be altered.

You must use Mozilla or another fully standards compliant browser (like Opera) to play MozTris.

JavaScript does not appear to be enabled, or your browser does not support the level of JavaScript required to play this game.

Use "low quality" graphics.


  • Left / Right - move piece left/right
  • Up - rotate piece
  • Down - increase fall speed (while held)
  • Space - pause game

MozTris is valid HTML 4.01 strict and uses valid CSS. Eventually, it may even work in other fully standard compliant browsers such as Konqueror, but right now, it does not seem to. If you can make it work in any other browser, send me a patch. I'd be interested!

Coming Soon

There will probably be a 1.3 release that readds the background images.

The planned 2.0 version will include new scoring methods like combos for clearing many lines rapidly and bonuses for clearing the screen.

A later version may include high scores.