Free Tetris. Stack falling blocks, clear four lines at a time and chase a high score. The original Javascript Tetris by Jake Gordon, running in your browser with no download and no sign-up.
Originally by Jake Gordon · MIT licence · source
Left and right arrows move the falling block, up arrow rotates it and down arrow drops it faster. Complete a horizontal row of blocks to clear it.
Yes. It runs entirely in your browser with no download, no account and no payment.
Javascript Tetris by Jake Gordon, open sourced under the MIT licence. See the credits page for details.