A fully playable version of the ancient board game Go, built with vanilla HTML, CSS, and JavaScript. Play a friend on the same screen or take on the built-in computer opponent — on desktop or mobile, online or offline.
▶ Play it: https://brett-buskirk.github.io/go/
Go is a territory game for two players, Black and White, on a 13×13 grid. Players take turns placing stones on the intersections; once placed, a stone never moves, but it can be captured.
- A group of connected stones is captured and removed when the opponent fills its last liberty (empty adjacent point).
- When neither player wants to play on, both pass and the territory is counted to decide the winner.
In this example the Black stones surround three White stones, capturing them and gaining the territory.
- Complete rules engine — captures, liberties, the suicide rule, and the ko (repetition) rule, plus pass, resign, and game-over detection.
- Territory scoring — when both players pass, the game enters scoring mode: territory is detected automatically, you click any dead stones to remove them, and a live score is shown using area scoring with komi.
- Play against the computer — choose your color and a difficulty:
- Easy — a fast heuristic bot that captures, defends its groups, and keeps its eyes.
- Hard — a Monte Carlo Tree Search (MCTS) opponent that plays out thousands of games to pick its move.
- Two-player mode — pass and play on a single device.
- Built-in rules guide — a Rules button explains everything for newcomers.
- Modern, responsive design — a clean board that scales from desktop down to phones.
- Installable PWA — add it to your home screen and play offline.
- Open the game and pick Two players or vs Computer (and your color/level).
- Click an empty intersection to place a stone. Black moves first.
- Surround enemy groups to capture them; avoid suicide and illegal ko moves.
- When the game winds down, click Pass twice to score. Mark any dead stones, read the final score, and start a New Game.
No build step or dependencies — it's plain static files. Either open index.html directly, or serve the folder over HTTP (recommended, so the service worker and offline support work):
python3 -m http.server
# then visit http://localhost:8000Vanilla HTML / CSS / JavaScript with jQuery, a generated SVG board, and a service worker for offline play. Hosted on GitHub Pages.
Released under the MIT License.