Chess
By Frank Force · MIT license. Source · All credits
About Chess
A full game of chess against the computer, with legal move highlighting so you can see where a piece can actually go before you commit. Castling, en passant and promotion are all handled, and the board reads clearly on a phone screen.
How to play
Tap a piece to pick it up, then tap the square you want it on.
Rules of Chess
- Each player starts with sixteen pieces: eight pawns, two rooks, two knights, two bishops, a queen and a king. White moves first.
- Pawns move one square forward, or two on their very first move, but they capture diagonally. Rooks move in straight lines, bishops diagonally, and the queen does both. Knights jump in an L shape and are the only piece that can pass over others.
- The king moves one square in any direction and may never move into check.
- Castling moves the king two squares toward a rook and jumps that rook over it. It is legal only if neither piece has moved, the squares between are empty, and the king is not in check or passing through it.
- En passant: if a pawn advances two squares and lands beside an enemy pawn, that pawn may capture it as though it had only moved one, but only on the very next move.
- A pawn reaching the far rank promotes, almost always to a queen.
- Checkmate wins the game. Stalemate, where the side to move has no legal move but is not in check, is a draw, as is threefold repetition or fifty moves without a capture or pawn move.
- A pawn reaching the far rank promotes, and you choose what it becomes: queen, rook, bishop or knight. It does not silently make a queen for you, so an underpromotion to a knight is available when that is the move.
- En passant is implemented. A pawn that has just advanced two squares can be captured by an enemy pawn beside it, as though it had only moved one, and only on the immediately following move.
Controls
- Tap a piece to pick it up
- Tap the square you want it on
What makes it worth playing
- A full game against the computer
- Legal moves are highlighted before you commit
- Castling, en passant and promotion all handled
- The board stays readable on a phone
Screenshots
Captured from this build on 2026-08-26.
Tips from playing it
- Get your knights and bishops out before moving the same piece twice.
- Castle early. A king in the middle is the most common way to lose quickly.
- Before every move, check what your opponent's last move attacked.
Why this game is here, and what we changed
Picked from the MIT-licensed LittleJS Arcade by Frank Force after checking the licence at source rather than trusting the repository label, and after confirming the game makes no requests to any other site. We host it on our own servers, so it loads straight into the game with no third-party ad code and no pre-roll video. We played it through on a real phone-sized screen on 2026-08-26 before publishing this page, and the screenshots above are from that session rather than from the original project.
More on how we pick and fix these: what we changed in the open-source games and how we test a game.
- Category
- Board
- Plays in
- Your browser, no download
- Orientation
- Portrait
- Players
- One player against the computer at three difficulty levels, or two players sharing one device.
- Difficulty
- As hard as chess has ever been
- Typical session
- 10 to 25 minutes a game
- Last tested by us
- 2026-08-26
- Created by
- Frank Force (MIT)
