Random Go Game Generator

Simulates a configurable number of Go moves by placing stones alternately (black first) on random empty points, skipping already-occupied points. A simplified capture check runs after each move: if an adjacent lone enemy stone (one not connected to any other same-color stone) just lost its last liberty, it is removed. Full multi-stone group liberties, suicide, and ko are not evaluated — see limitations. A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-26

Overview

Introduction

This tool plays out a sequence of random Go moves, alternating black and white, starting from an empty board of a configurable standard size.

Rather than implementing the full rule set, it uses a deliberately simplified capture check so the simulation still produces occasional, genuine captures without the complexity of tracking arbitrary-sized group liberties.

What Is Random Go Game Generator?

A random Go game simulator that places stones alternately on random empty points and applies one simplified capture rule after each move.

Output is a move list in standard Go point notation (e.g. 'B D4', 'W Q16') plus the resulting board.

How Random Go Game Generator Works

Each move picks a uniformly random point from the currently empty points and places the side-to-move's stone there, alternating black and white starting with black.

After placement, each of the four orthogonally adjacent points is checked: if it holds an opposing stone that has no same-color neighbor of its own (a 'lone' stone, not part of a larger connected group) and that stone's liberties just dropped to zero, it is captured and removed.

This repeats for the requested move count, or until the board completely fills up, whichever comes first.

When To Use Random Go Game Generator

Use it to generate a sample Go move sequence for testing a board-rendering or SGF-like move-list UI.

Useful for demonstrating basic Go placement and a simplified capture mechanic without a full rules engine.

Features

Advantages

  • Produces genuine, if limited, captures rather than never removing any stone at all.
  • Supports all three standard board sizes (9x9, 13x13, 19x19).
  • Runs entirely client-side and regenerates instantly with a configurable move count.

Limitations

  • Only lone (unconnected) enemy stones can ever be captured — a placement that removes the last liberty of a multi-stone group does nothing, since group liberties are never computed.
  • Suicide moves are not prevented; a stone can be placed into a position with zero liberties.
  • The ko rule is not tracked, so board states that a real game would forbid repeating can reappear here.
  • Move selection is uniformly random with no strategic evaluation, so games look nothing like real play.

Examples

A 20-move random game

Input

(no input; generated from settings)

Output

B E5, W C3, B G7, W D4 (captures C3), ...

Moves alternate; a capture note appears only when the simplified lone-stone rule triggers.

Final board summary

Input

(no input; generated from settings)

Output

18 stones remaining after 20 moves (2 captured)

Captured stones are removed from the board and freed up as empty points again.

Best Practices & Notes

Best Practices

  • Use a smaller board (9x9) if you want captures to happen more often relative to move count, since points are more likely to end up surrounded on a smaller grid.
  • Don't treat the output as a realistic Go game — random placement produces very different patterns than actual play.

Developer Notes

Board representation and text rendering are imported from the same shared go-board module used by the position generator; the lone-stone capture check specifically avoids a full flood-fill group/liberty algorithm to keep the simulation simple, as documented in the limitations.

Random Go Game Generator Use Cases

  • Generating sample move sequences for testing a Go board UI
  • Demonstrating a simplified capture mechanic without a full rules engine
  • Producing placeholder Go game data for a prototype or demo

Common Mistakes

  • Expecting a placement that surrounds a multi-stone group to capture it — only lone, unconnected stones are ever captured here.
  • Assuming the move sequence reflects real Go strategy — placement is uniformly random.

Tips

  • Try a 9x9 board for more frequent, visible captures within a shorter move count.
  • Check `capturesCount` alongside the move list to see how many simplified captures occurred in a given game.

References

Frequently Asked Questions