Connect blocks to define piece movement, capture rules, and conditional triggers — no coding. Think Scratch, but for chess rules. Supports leapers, riders, and complex fairy piece behaviour. Not presets — actual customizability.
Custom Pieces & Boards
Design pieces with unique sprites, define any movement pattern, and build boards of any shape — rectangular, hexagonal, or custom-cut topologies. Every rule is yours to define.
Stockfish Analysis
Your custom game is evaluated by the Stockfish engine — even when the rules are completely non-standard.
Instant Multiplayer
Generate a room link and share it. Your opponent joins in their browser, no install needed. Playtest a new variant in minutes.
Help cover hosting
Buy Me a Coffee
Chessperiment costs about €15/month to keep online. If it helped you build, test, or play something fun, you can chip in.
Voluntary support via Buy Me a Coffee. External checkout.