Interactive chess board. Click to move, full rules (castling, en passant, promotion), undo, flip board, copy FEN/PGN, and play Stockfish 16. Powered by chess.js (BSD-2).
International Chess Board
How to use
Click a piece
The piece highlights and all legal moves appear as dots (empty squares) or rings (captures).
Click a destination
The move plays instantly. Special moves (castling, en passant) are handled automatically. Promotion prompts you to pick a piece.
Undo or flip
↶ Undo takes back any move. ⇅ Flip rotates the board for the other side's perspective.
Export or load
Copy the FEN (current position) or PGN (game record) to share. Paste a FEN into the "Load" box to jump to any position.
Interactive Chess Board — Play, Study, Share
This is a fully interactive chess board powered by chess.js — the same rule engine used by Lichess.org, Chess.com training tools, and countless open-source chess apps. Every rule of standard FIDE chess is enforced: castling kingside (O-O) and queenside (O-O-O), en passant captures, pawn promotion to any piece, three-fold repetition draws, fifty-move-rule draws, stalemate detection, and check/checkmate.
What this tool is good for
Playing out positions: Paste a FEN from a book, puzzle, or online game and continue from there. Annotating openings: Step through your preparation move by move and copy the PGN. Two-player play: No internet, no account, no app — just open the page and pass the device. Engine practice: Play Stockfish 16 at difficulty 0–20. Teaching: Show legal-move highlights to students learning piece movement.
"Chess's game-tree complexity (the Shannon number, ~10¹²⁰) far exceeds the number of atoms in the observable universe (~10⁸⁰). The count of legal positions is smaller — about 10⁴⁴ — and still beyond exhausting."
Chess in Asia and Singapore
Chess (the international Western variant — distinct from Xiangqi 中国象棋) has grown rapidly in Asia. Singapore produced GM Tin Jingyao (b. 2000) and IM Goh Wei Ming. Malaysia's GM Yeoh Li Tian became the country's first grandmaster in 2018. The Singapore Chess Federation runs national leagues and the annual Singapore Chess Festival. The ASEAN Chess Confederation hosts inter-school and youth championships annually rotating between SG, MY, ID, PH, TH, VN.
Privacy and self-hosting
Everything runs in your browser — your position is never sent to a server. The Stockfish 16 engine used for computer play runs locally via WebAssembly, so nothing leaves your device there either. For deeper analysis, copy your FEN/PGN into Lichess Studies or your favourite desktop engine. The board logic library (chess.js, ~80KB, BSD-2 licensed) is self-hosted on our own domain. Stockfish 16 is free software under the GNU General Public License v3; we redistribute the WebAssembly build unmodified, and its complete source is at github.com/official-stockfish/Stockfish.
10 Facts about Chess
Chess is ~1,500 years old. The earliest direct ancestor — Chaturanga — was played in 6th-century India. It travelled to Persia (Shatranj), then to the Islamic world, then to Europe by ~1000 CE.
The modern queen was introduced around 1475 in Spain — replacing the much weaker ferz (1-square diagonal mover) of medieval chess. Same era as Columbus.
FIDE (Fédération Internationale des Échecs) was founded in Paris in 1924 and now has 200+ member federations — more than FIFA.
Magnus Carlsen held the highest official Elo rating ever: 2882 in May 2014. He retained the World Championship from 2013 to 2023 before declining to defend in 2024.
The Shannon number (~10¹²⁰) estimates chess's game-tree complexity; the count of legal positions is about 10⁴⁴. By comparison, Go's game-tree complexity is ~10³⁶⁰.
The longest theoretically possible chess game under FIDE rules is 5,898.5 moves (constrained by 50-move and 3-fold repetition rules — both refreshed by pawn moves and captures).
Castling appeared in modern form only in the 17th century. Earlier forms allowed the king to "leap" up to 3 squares. Today's rules: king moves 2 squares toward rook, rook jumps over.
En passant ("in passing", French) was added when pawns gained the 2-square first move (15th century) — to preserve the old capture dynamics. Most-forgotten rule among club players.
Singapore's GM Tin Jingyao (born 2000) earned the GM title in 2021, becoming Singapore's 2nd grandmaster after Wong Meng Kong. Studied math at NUS while competing internationally.
Lichess.org — the world's largest free chess server — serves 5+ million games per day and is open-source. Founded 2010 by Thibault Duplessis as a "computer science final-year project".
Frequently Asked Questions
Yes — switch Mode to "🤖 vs Computer" and Stockfish 16 (the world's strongest open-source chess engine) plays you. Pick your colour, set difficulty 0-20 (0 ≈ beginner, 20 ≈ ~2500 Elo without NNUE — still way beyond any casual human). The engine runs entirely in your browser via WebAssembly; nothing leaves your device.
Click your king, then click two squares toward the rook (kingside:
e1→g1ore8→g8; queenside:e1→c1ore8→c8). The rook jumps over automatically. Castling is only legal if neither piece has moved, no squares between are attacked, and the king isn't in check.When a pawn reaches the 8th (white) or 1st (black) rank, a prompt asks which piece to promote to — Queen (q), Rook (r), Bishop (b), or Knight (n). Default is Queen. Underpromotion to a knight is the classic exception that wins puzzles.
When an opponent's pawn advances 2 squares and lands beside your pawn, you can capture it as if it had moved only 1 square. You must do it on the very next move — the chance vanishes after that. The tool prompts via legal-move highlight.
Copy the PGN (Portable Game Notation) text from the side panel. Paste it into a text file, into Lichess Studies, or back into this tool any time. PGN is the universal chess game format — supported everywhere.
Forsyth-Edwards Notation — a compact text string describing any chess position, including whose turn it is, castling rights, en passant square, and move counts. Example:
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1is the starting position.Not yet — this version is untimed. Real-time clock controls are common in dedicated chess servers (Lichess, Chess.com). For tournament/blitz play, use one of those.
Yes — chess.js (the engine powering this board) implements every FIDE rule including triple repetition, 50-move draws, insufficient material draws, and detects checkmate/stalemate. It does NOT enforce the touch-move rule (over-the-board only).
We use Unicode chess glyphs (♔♕♖♗♘♙♚♛♜♝♞♟) — they're font-rendered, accessible to screen readers, work without image downloads, and scale perfectly. Modern browsers all render them well.
Yes. RECATOOLS is supported by ads and never charges for tools. The chess.js library is BSD-2 licensed (free to use commercially). No account, no signup, no tracking pixels.
Method & sources
How it computes
Legal-move generation, check and mate detection, castling rights, en passant, promotion, stalemate and threefold repetition are all handled by the vendored chess.js engine. The board reads a position, asks the engine what is legal, and renders the result; positions export as FEN and games as PGN. No engine evaluation and no opponent — this is a board, not a computer player.
What this tool implements
- Full rules as implemented by chess.js: castling with its rights, en passant, promotion, check, checkmate, stalemate and threefold repetition. Legality is decided by the engine rather than by the interface, so an illegal move cannot be made by clicking carefully.
- Positions are exported as FEN and games as PGN — the standard interchange formats — so a position here can be pasted into any other chess program.
- No engine evaluation, no move suggestion and no opponent. It is a board for playing out or setting up positions.
Sources
- chess.js v1.4.0, BSD-2-Clause: https://github.com/jhlywa/chess.js — the move generation and rules engine. Vendored locally and loaded as an ES module; nothing is fetched at request time.
- FIDE Laws of Chess: https://handbook.fide.com/chapter/E012023 — the rules chess.js implements, including the threefold-repetition and stalemate conditions this board reports.
What can make this go out of date
- chess.js is vendored at v1.4.0 and nothing refetches it. A rules correction upstream reaches this page only on a manual update.
Pick up where you left off
Stored only in this browser — never sent to our servers.