Conway's Game of Life

Click or drag on the grid to bring cells to life. Or drop in something pre-built:

How it works

Every cell looks at its eight neighbours and follows four rules: a live cell with fewer than two neighbours dies of loneliness, one with two or three carries on, one with more than three dies of overcrowding, and any dead cell with exactly three neighbours springs to life. That's the entire program. Nobody plays it - you set the first frame and then watch.

The interesting part is what falls out of those rules. Gliders walk diagonally across the board forever, pulsars breathe on a fifteen step cycle, and the glider gun quietly manufactures new gliders every thirty generations. None of that is coded anywhere; it's just four rules meeting a grid. The edges here wrap around, so anything that walks off the right hand side reappears on the left.