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 or a PGN game into the "Load" box to set up any position or replay a game.
Interactive Chess Board — Play, Study, Share
This is a fully interactive chess board. Which moves are legal is decided by chess.js, an open-source move generator, so castling kingside (O-O) and queenside (O-O-O), en passant, promotion to any piece, check and checkmate all follow the rules. How a game ends follows the FIDE Laws of Chess in force from 1 January 2023: checkmate, stalemate and a dead position end it at once; a position appearing for the third time, or 50 moves by each side without a capture or a pawn move, lets the player to move claim a draw (a button appears beside the board); and a fivefold repetition, or 75 such moves, ends it drawn with no claim needed.
What this tool is good for
Playing out positions: Paste a FEN or a PGN game 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 is the Shannon number: Shannon (1950) estimated about 10¹²⁰ variations from the opening position, and worked out that a machine checking one every microsecond would need over 10⁹⁰ years just for its first move. Even the legal positions number about 4.8 × 10⁴⁴ (Tromp)."
Chess in Singapore and Malaysia
Chess (the international Western variant — distinct from Xiangqi 中国象棋) has strong players across South-East Asia. Singapore's grandmasters include Wong Meng Kong, Kevin Goh Wei Ming and Tin Jingyao (born 2000), and Malaysia has GM Yeoh Li Tian — each title as listed in FIDE's rating database. The Singapore Chess Federation runs the National Championships and the National Age Group Chess Championships.
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 1.4.0, 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.
The queen only became powerful in the late 1400s
The earliest written mentions of chess date from about the start of the 7th century CE and point to north-west India and Persia, where the pieces were a king, a counsellor, two elephants, two horses, two chariots and eight foot-soldiers (H. J. R. Murray, A History of Chess, 1913).
The modern queen is a late-15th-century invention: she replaced the medieval fers, which moved one square diagonally. Von der Lasa dated the change to about 1475; Murray (1913) put it no earlier than 1485 and thought Italy had a better claim to it than Spain.
FIDE (Fédération Internationale des Échecs) was founded in Paris in 1924; it now counts 204 national federations as members.
Magnus Carlsen's peak on FIDE's standard rating list is 2882, first reached in May 2014 and matched in August 2019.
The Shannon number: Claude Shannon's 1950 paper estimated about 10¹²⁰ variations from the opening position and roughly 10⁴³ possible positions; John Tromp's later count puts the legal positions at about 4.8 × 10⁴⁴.
Two draws must be claimed, two are automatic. Under FIDE's Laws a threefold repetition, or 50 moves each without a capture or pawn move, only entitles the player to move to claim a draw; a fivefold repetition or 75 such moves ends the game drawn on the spot (Articles 9.2, 9.3 and 9.6).
Castling settled into its modern form slowly. Murray (1913) records the modern move in ordinary use in Rome by 1585, while other Italian cities still allowed older king leaps, or no castling at all, into the 1600s.
En passant came with the pawn's double first step: by the close of the 15th century a pawn on its fifth rank could take an enemy pawn that had just stepped past it — though, Murray notes, Italian players long refused the rule.
Promotion is not limited to captured pieces. FIDE's Article 3.7.3.4 lets a pawn become a second queen (or a third) while the first is still on the board — this board allows it too.
Lichess.org, the free, open-source chess server, began in 2010 as a hobby project by Thibault Duplessis; by its own count its users now play more than five million games a day.
Frequently Asked Questions
Yes — switch Mode to "🤖 vs Computer" and Stockfish 16, a free, open-source engine, plays you. Pick your colour and set the difficulty from 0 to 20: that is Stockfish's own Skill Level option, and the page also limits each search (from depth 3 at level 0 to depth 15, and 0.2 to 1.8 seconds a move), so even level 20 here is well short of the engine's full strength. 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 legal only if neither the king nor that rook has moved, every square between them is empty, and the king is not in check and does not pass through or land on an attacked square (FIDE Article 3.8.2).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). It is pre-filled with q, so OK makes a queen; Cancel takes the move back. You may promote to a piece you still have, so two queens are legal. 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's Load box any time to replay the game. 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. After a two-square pawn move the copied FEN names the en passant square, as the 1994 PGN standard specifies, even when no capture is possible.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.
Every move rule, yes — legality comes from chess.js. The draws follow the FIDE Laws: stalemate and a dead position end the game at once (the dead positions recognised are the insufficient-material ones, such as king against king and bishop); a threefold repetition or 50 moves each without a capture or pawn move brings up a "Claim draw" button, because Articles 9.2 and 9.3 make those draws a claim, not automatic; and a fivefold repetition or 75 such moves ends the game drawn on its own (Article 9.6). 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 and no signup.
Method & sources
How it computes
Move legality from the vendored chess.js 1.4.0, checked against the Chess Programming Wiki perft counts. Game endings follow the FIDE Laws (2023): checkmate, stalemate and a dead position end the game; threefold repetition and the 50-move rule are draws the player to move may claim; fivefold repetition and 75 moves are automatic draws. FEN and PGN export follow the 1994 PGN standard. Optional Stockfish 16 opponent runs in the browser (ChessNotationKernel).
What this tool implements
- Which moves are legal is decided by chess.js 1.4.0, not by the interface. Its move generator is checked against the Chess Programming Wiki perft counts: 20, 400 and 8,902 positions at depths 1-3 from the start; 48 and 2,039 for Kiwipete; and positions 3, 4 and 5.
- How a game ends follows the FIDE Laws of Chess in force from 1 January 2023: checkmate (5.1.1), stalemate (5.2.1) and a dead position (5.2.2) end it at once; a third appearance of the same position (9.2) or 50 moves by each player without a capture or pawn move (9.3) let the player to move claim a draw with a button; a fifth appearance (9.6.1) or 75 such moves (9.6.2, a checkmate on that move taking precedence) end it drawn without a claim.
- Repetition uses the 9.2.3 identity: same player to move, same pieces on the same squares, same castling rights and the same en passant possibility. The dead positions recognised are the insufficient-material ones (king against king, king and minor piece against king, bishops all on one colour); other dead positions, such as locked pawn chains, are not detected.
- The copied FEN names the en passant square after every two-square pawn move, as the PGN standard (revised 1994.03.12, 16.1.3.4) specifies; the copied PGN carries the Seven Tag Roster with a Result tag equal to the movetext's termination marker (8.1.1.7). A FEN or a PGN game pasted into the Load box sets the board up again.
- The computer opponent is Stockfish 16 (GPL-3.0) as a single-threaded WebAssembly build in the browser. Difficulty 0-20 is Stockfish's Skill Level option, and each search is also capped at depth 3-15 and 0.2-1.8 seconds a move, so level 20 here is not the engine's full strength.
- Corrected 2026-10-19: the board stopped the game at a threefold repetition or 50 moves (FIDE: a claim) and never at fivefold or 75 (FIDE: automatic); the copied PGN read [Result "*"] after a checkmate; the copied FEN dropped the en passant square; the castling answer said no square between king and rook may be attacked (b1 may be, on the queenside); the page said a PGN could be pasted "back into this tool", which had no PGN import; chess.js was called the rule engine Lichess uses; Kevin Goh Wei Ming was called an IM (FIDE lists him a GM); Tin Jingyao was called Singapore's second grandmaster and Carlsen champion until a 2024 refusal (both unsourced; removed); FIDE was said to have more members than FIFA (204 against 211); the modern queen was dated "around 1475 in Spain" and chess to 6th-century India (Murray 1913: no earlier than 1485, and the earliest records about 600 CE); a quoted Lichess origin and a Stockfish Elo figure had no source; and this record said the board had no opponent.
Sources
- FIDE. Laws of Chess taking effect from 1 January 2023 (Articles 3.7.3, 3.8.2, 5.1.1, 5.2.1, 5.2.2, 9.2, 9.3, 9.6): https://handbook.fide.com/chapter/E012023
- Chess Programming Wiki. Perft Results (initial position, Kiwipete, positions 3-5): https://www.chessprogramming.org/Perft_Results
- Edwards SJ, et al. Standard: Portable Game Notation Specification and Implementation Guide. Revised 1994.03.12 (8.1.1.7 Result tag; 16.1 FEN): https://www.thechessdrum.net/PGN_Reference.txt
- chess.js v1.4.0, BSD-2-Clause — move generation, vendored and loaded as an ES module: https://github.com/jhlywa/chess.js
- Stockfish 16, GPL-3.0 — source: https://github.com/official-stockfish/Stockfish
- Shannon CE. Programming a computer for playing chess. Philosophical Magazine. 1950;41(314) — about 10^120 variations; roughly 10^43 positions: https://vision.unipv.it/IA1/ProgrammingaComputerforPlayingChess.pdf
- Tromp J. ChessPositionRanking — legal positions estimated at (4.82 ± 0.03) × 10^44: https://github.com/tromp/ChessPositionRanking
- Murray HJR. A History of Chess. Oxford: Clarendon Press; 1913 — earliest records (c. 600 CE), the new queen (pp. 777-778), en passant and castling: https://archive.org/details/AHistoryOfChessHJRMurray
What can make this go out of date
- The FIDE Laws are revised from time to time; the endings here are the 1 January 2023 text. FIDE's member count, Lichess's games per day and the players' titles are as read on 2026-10-19.
Abridged — the full review record for this tool runs longer than the list above.
Pick up where you left off
Stored only in this browser — never sent to our servers.