FEN notation

A single line of text encoding a whole chess position.

Also known as: Forsyth-Edwards notation, Position string

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Meanings

Forsyth-Edwards notation packs an entire chess position into one line: the pieces rank by rank, whose move it is, castling rights, en passant, and two counters. It records everything needed to resume a game, which a diagram alone does not.

Officially standardisedVerified fact
Encodes a complete chess position as a single line of text, including side to move, castling rights and move counters.
Contexts: History
Officially standardisedVerified fact
Carries information a diagram cannot, since castling rights and en passant possibility depend on history rather than on where the pieces stand.
Contexts: History

Visual description

A single line of letters, numerals and slashes, written without spaces between its rank groups.

Symmetry: none
Orientation: upright

Confidence

IdentityHigh confidence: High confidence because the identity is documented in encyclopedic references, but multiple independent sources agree.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but multiple independent sources agree, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is documented in encyclopedic references, but multiple independent sources agree.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references, but multiple independent sources agree.

Sources

FIDE Laws of Chess, Appendix C: Algebraic Notation
Fédération Internationale des Échecs (FIDE) · retrieved 2026-08-02
The governing body's own handbook. Authoritative for the notation FIDE requires in competition — the piece letters, the capture and check marks, castling — and for nothing outside it. Annotation symbols expressing an opinion about a move are deliberately absent from the Laws and are not cited here.
Go (game)
Wikipedia · retrieved 2026-08-22
Tertiary reference, cited for the conventional description of a mark, its usual name and where it is encountered. Where an issuing body defines the mark, that body is cited alongside and governs.
Algebraic notation (chess)
Wikipedia · retrieved 2026-08-02
Tertiary reference. Cited for how a mark is written and read in ordinary practice, and for conventions no governing body issues. Never cited for a claim that a rule says something — the rulebooks below carry those.
Go rules and notation
Nihon Ki-in · retrieved 2026-08-23
The Japanese Go association, one of the bodies whose rules are in international use. Go has more than one rule set — Japanese, Chinese and AGA scoring differ — and records say where a claim is rule-set specific.

Last reviewed 2026-08-23

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Board game and score notation

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Meanings

Officially standardisedVerified fact

Encodes a complete chess position as a single line of text, including side to move, castling rights and move counters.

Contexts: History

Officially standardisedVerified fact

Carries information a diagram cannot, since castling rights and en passant possibility depend on history rather than on where the pieces stand.

Contexts: History

Confidence

IdentityHigh confidence: High confidence because the identity is documented in encyclopedic references, but multiple independent sources agree.
Historical originModerate confidence: Moderate confidence because the historical origin is documented in encyclopedic references, but multiple independent sources agree, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Current useHigh confidence: High confidence because the current use is documented in encyclopedic references, but multiple independent sources agree.
Visual matchHigh confidence: High confidence because the visual match is documented in encyclopedic references, but multiple independent sources agree.

Sources

FIDE Laws of Chess, Appendix C: Algebraic Notation
Fédération Internationale des Échecs (FIDE) · retrieved 2026-08-02
The governing body's own handbook. Authoritative for the notation FIDE requires in competition — the piece letters, the capture and check marks, castling — and for nothing outside it. Annotation symbols expressing an opinion about a move are deliberately absent from the Laws and are not cited here.
Go (game)
Wikipedia · retrieved 2026-08-22
Tertiary reference, cited for the conventional description of a mark, its usual name and where it is encountered. Where an issuing body defines the mark, that body is cited alongside and governs.
Algebraic notation (chess)
Wikipedia · retrieved 2026-08-02
Tertiary reference. Cited for how a mark is written and read in ordinary practice, and for conventions no governing body issues. Never cited for a claim that a rule says something — the rulebooks below carry those.
Go rules and notation
Nihon Ki-in · retrieved 2026-08-23
The Japanese Go association, one of the bodies whose rules are in international use. Go has more than one rule set — Japanese, Chinese and AGA scoring differ — and records say where a claim is rule-set specific.

Last reviewed 2026-08-23