Underpopulation
A live cell with 0-1 neighbors dies.
Tip: click or drag to toggle cells • Shift = erase • Ctrl/⌘ = draw • Pan mode drags the view • keyboard: arrows move, Space/Enter toggle
Load classic patterns instantly, including still lifes, oscillators, spaceships, guns, puffers, methuselahs, and growth patterns.
Stable patterns such as Block, Beehive, Loaf, Boat, and Tub do not change from one generation to the next.
Oscillators repeat on a fixed cycle. Try Blinker, Toad, Beacon, Pulsar, and Pentadecathlon to compare periods.
Spaceships translate across the grid. Glider, LWSS, MWSS, and HWSS are useful starting points for motion and signal experiments.
Gun patterns emit moving objects again and again. Gosper Glider Gun and Simkin Glider Gun demonstrate long-running growth.
Methuselahs are small seeds that take a long time to settle. R-pentomino, Diehard, and Acorn are classic stress tests.
Growth patterns keep creating activity on large boards. Breeder-style seeds and switch engines are good examples to explore with zoom and pan.
Paste an RLE pattern, Life 1.06 file, or plaintext pattern to load it into the simulator. Export your current board as RLE, PNG, SVG, or a shareable URL.
Supported: RLE, Life 1.06 coordinate files, and plaintext with O/#/1 for live cells.
RLE and SVG are copied into this box for reuse.
Each generation checks the eight neighboring cells around every square and applies four simple outcomes.
A live cell with 0-1 neighbors dies.
A live cell with 2-3 neighbors survives.
A live cell with 4+ neighbors dies.
A dead cell with exactly 3 neighbors becomes alive.
This simulator runs fully client-side in your browser. You can explore Conway’s Game of Life and related rules, save/share board states by URL, and now also share snapshots as images.
Conway’s Game of Life is a playful, visual way to explore how complex behavior can emerge from simple rules. It is a grid-based simulation where each square, or cell, is either alive or dead. At each step, the grid updates based only on the local neighborhood around every cell. Even though the rules are minimal, the system can produce surprising patterns like moving “gliders,” repeating oscillators, and intricate long-term structures. This simulator lets you watch those patterns unfold in real time and experiment with different starting designs.
The classic Game of Life uses the rule set called B3/S23. That shorthand means a dead cell is born if it has exactly three live neighbors, and a live cell survives if it has two or three neighbors. Any other case dies off. Because every update is simultaneous, the grid behaves like a tiny world with its own physics. It is a great introduction to cellular automata, emergence, and rule-based systems often discussed in computer science, mathematics, and complexity science.
Beyond being fun to watch, the Game of Life is a classic example of emergent behavior. Researchers and educators use it to illustrate how local rules can create global structure, a concept that appears in topics like ecology, network theory, and artificial life. It also has historical importance in computer science: the Game of Life is known to be computationally universal, meaning it can simulate logic and computation with the right patterns. For students, it is a hands-on way to build intuition about algorithms, discrete time steps, and simulation modeling. This version runs entirely in your browser, so your designs stay private and the experience is instant.
External links open in a new tab. Not affiliated with Starlight Tools.
It is an online cellular automaton simulator where you draw live cells on a grid and watch each generation update under Conway’s rules or another Life-like rule set.
Use the Glider preset in the pattern library, or draw the five-cell diagonal glider shape and press Play.
The Gosper Glider Gun is a famous pattern that repeatedly emits gliders, creating unbounded growth on a large enough board.
B3 means a dead cell is born with exactly three live neighbors. S23 means a live cell survives with two or three live neighbors.
Yes. Some patterns vanish, some stabilize, and some keep producing activity indefinitely.
Yes. With suitable patterns, Life can represent logic and computation, making it Turing complete.
Yes. Paste RLE into the import box and use Import Pattern.
Yes. Export as RLE, SVG, PNG, or a shareable URL.
Wrap connects opposite edges of this finite board. An infinite grid keeps expanding without borders.
The tiny five-cell glider drifts diagonally forever, advancing one cell every 4 generations—first proof that Life supports self-moving “spaceships.”
The Gosper Glider Gun (a preset here) spits out a new glider every 30 generations. Its discovery in 1970 was the first pattern with unbounded growth.
Five cells placed as the R-pentomino thrash around for 1,103 generations before settling into 116 still lifes and oscillators—try it from the Examples row.
With glider streams as signals, Life can build logic gates, memory, even full CPUs. Your browser grid can, in theory, simulate any computation.
Enable Wrap and the grid becomes a torus: gliders loop endlessly instead of escaping, and some “dying” patterns become oscillators.