Draw live cells on the grid and watch them evolve by Conway's simple birth and survival rules. Load classic patterns such as gliders, spaceships and the Gosper glider gun, change the speed or rule, and import or export patterns in the standard RLE format.
Last updated:
Generation0
Population0
Click or drag on the grid to draw. Click a live cell to erase.
RLE import / export
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How to use the Conway's Game of Life
Draw cells by clicking or dragging on the grid. Clicking a live cell erases instead.
Press Start to run the simulation, or Step to advance one generation at a time. Space and N do the same when the grid has focus.
Pick a pattern from the library and press Load pattern, or switch on Stamp to place copies wherever you click.
Adjust the speed, grid size, edges and rule in the side panel to experiment.
Share a pattern by exporting the grid as RLE, or paste RLE from a pattern collection and press Import.
How the Game of Life works
The Game of Life is a zero-player game: once you set up the starting cells, the rules decide everything that happens next. All cells update at the same moment, based only on how many of their eight neighbours (horizontal, vertical and diagonal) are alive in the current generation.
Cell now
Live neighbours
Next generation
Nickname
Alive
0 or 1
Dies
Underpopulation
Alive
2 or 3
Stays alive
Survival
Alive
4 to 8
Dies
Overcrowding
Dead
Exactly 3
Becomes alive
Birth
Dead
Any other number
Stays dead
–
With the Color newborn cells option, cells born in the latest generation are shown in orange, so you can see where the action is.
Families of patterns
Type
What it does
Examples in the library
Still life
Never changes
Block, beehive, loaf, boat
Oscillator
Returns to its starting shape after a fixed number of generations (its period)
A tiny start that evolves for a very long time before settling
R-pentomino (1,103 gens), acorn (5,206 gens), diehard (dies at 130)
Tips for experimenting
Give patterns room. Methuselahs like the acorn need a large grid with dead edges; on a small or wrapped grid their debris collides and the result changes.
Collide gliders. Stamp two gliders heading toward each other (use Rotate and Flip) and step through the crash one generation at a time.
Use Reset. After a run, Reset brings back the exact pattern you started from, so you can try again at a different speed.
Save your discoveries. Export the grid to RLE and keep the text; importing it later restores the pattern and its rule.
Frequently asked questions
What are the rules of Conway's Game of Life?
Each cell on the grid is alive or dead and has eight neighbours. In every generation a dead cell with exactly 3 live neighbours is born, a live cell with 2 or 3 live neighbours survives, and every other cell dies or stays dead. This rule is written B3/S23 (born on 3, survives on 2 or 3).
Who invented the Game of Life?
The British mathematician John Horton Conway devised it in 1970. It became famous after Martin Gardner described it in his Mathematical Games column in Scientific American in October 1970.
What is a glider gun?
A glider gun is a pattern that repeats itself while shooting out gliders forever. The Gosper glider gun, found by Bill Gosper in 1970, fires one glider every 30 generations. It proved that a finite pattern in Life can grow without limit.
What is RLE in the Game of Life?
RLE (run length encoded) is the standard text format for Life patterns. A header line gives the width, height and rule, then b means a dead cell, o a live cell, $ the end of a row and ! the end of the pattern, with numbers in front meaning repeats. For example the glider is bo$2bo$3o!.
What is the difference between dead and wrap-around edges?
With dead edges, everything outside the grid counts as dead, so patterns that reach the border are cut off and may break up. With wrap-around edges the grid behaves like a torus: a glider leaving on the right comes back on the left.
What are HighLife, Seeds and Day & Night?
They are other cellular automata that use the same grid with different birth and survival counts. HighLife (B36/S23) is like Life but has a small self-replicating pattern, Seeds (B2/S) explodes from almost any start, and Day & Night (B3678/S34678) treats live and dead regions symmetrically.
Why does my pattern behave differently than in other programs?
The most common reasons are the grid edge (a pattern that hits a dead border changes), a too small grid, or a different rule. Use a larger grid, check that the rule is B3/S23 and give spaceships room to travel.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.