Chess FEN Visualizer
Render a chess board from a FEN string.
Overview
The Chess FEN Visualizer renders a chess position from a Forsyth-Edwards Notation string, the compact text format used by every major chess engine, database, and online platform. Paste the FEN and you'll see the board, the side to move, castling rights, en-passant target, and the half-move and full-move clocks.
FEN is the standard way to share a position without sharing a whole game. Engines accept it as input, databases store puzzles in it, and chess writers paste it into articles so software can render the diagram automatically. Use this visualizer to inspect engine output, double-check a puzzle position, or sanity-check a custom-built starting position before loading it into your own software.
How it works
A FEN string has six space-separated fields. The first describes the board, scanning from rank 8 down to rank 1: each rank uses uppercase letters for white pieces (KQRBNP), lowercase for black (kqrbnp), and digits 1-8 to compress consecutive empty squares. Ranks are separated by forward slashes, so a complete board field has exactly seven slashes.
The remaining five fields encode active colour (w or b), castling availability (any subset of KQkq, or -), en-passant target square (algebraic coordinates or -), halfmove clock for the fifty-move rule, and the full move number. The visualizer parses each field, validates the rank/file counts, and draws the resulting position on a standard board.
Examples
- The initial position is
rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1. The board field places every piece, white is to move, both sides retain all castling rights. - After the move 1.e4:
rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1. Note the en-passant targete3. - An endgame K+P vs K:
8/8/8/4k3/8/4K3/4P3/8 w - - 0 1. Empty ranks compress to8. - The famous "Immortal Game" final position pastes cleanly into the visualizer to confirm Anderssen's mating net.
FAQ
Does the visualizer check whether the position is legal?
It checks rank and file counts and basic syntax, but legality (e.g. both kings present, no pawns on the first or eighth rank) is your responsibility.
Can it parse Shredder-FEN or X-FEN for Chess960?
This implementation handles standard FEN. Chess960 castling extensions are not supported.
What does the halfmove clock count?
Plies since the last pawn move or capture, used for the fifty-move draw rule (which triggers at 100 plies).
Why are some squares empty but described by a digit?
A digit n from 1 to 8 represents n consecutive empty squares on that rank.
Can I export the rendered board as an image?
Right-click the rendered board to copy or save it as an image, depending on your browser.