Laws of Chess - Chess960
Chess960 offers 960 possible starting positions.
The starting position Chess960 must meet the following rules:
pawns are placed on their orthodox home squares.
- All remaining
white pieces are placed on the first rank.
- The white
king is placed somewhere between the two white rooks.
- The white
bishops are placed on opposite-colored squares.
- The black
pieces are placed equal-and-opposite to the white pieces. For example,
if white's king is placed on B1, then black's king is placed on B8.
many differnet procedures for creating a starting position. Within myChess.de
the computer takes over this task if requested.
Once the initial position is set up, the rules for play are the same as
standard chess. Each player´s objective is to checkmate their opponent´s
Chess960 allows each player to castle once per game. However, castling
may only occur under the following conditions, which are extensions of
the standard rules for castling:
castling, the rook and king´s final positions are exactly the
same positions as they would be in standard chess. Thus, after A-side
castling (notated as O-O-O and known as queen-side castling in standard
chess), the King is on C (C1 for White and C8 for Black) and the Rook
is on D (D1 for White and D8 for Black). After H-side castling (notated
as O-O and known as king-side castling in orthodox chess), the King
is on G and the Rook is on F.
- All the
squares between the king´s initial and final squares (including
the final square), and all of the squares between the rook´s initial
and final squares (including the final square), must be vacant except
for the king and castling rook.
cannot capture any pieces.
- The king
and castling rook cannot "jump" over any pieces other than each other.
- A player
may castle at most once in a game. If a player moves his king or both
of his initial rooks without castling, he may not castle during the
rest of the game. Also he may not castle with a rook who has allready
- The king
may not be in check before or after castling.
- All of
the squares between the king´s initial and final squares (including
the initial and final squares) must not be under attack by any opposing
How to castle:
When playing Chess960 move the king by drag & over the field of the rook you want to
Recording the game
the initial position is usually not the orthodox chess initial position,
recorded games must also record the initial position. Games recorded using
the Portable Game Notation (PGN) can record the initial position using
Forsyth-Edwards Notation (FEN), as the value of the "FEN" tag. Castling
is marked as O-O or O-O-O, just as in standard chess. Note that not all
chess programs can handle castling correctly in Chess960 games (except
if the initial position is the standard chess initial position). To correctly
record a Chess960 game in PGN, an additional "Variant" tag must be used
to identify the rules; the rule named "Fischerandom" is accepted by many
chess programs as identifying Chess960.
FEN is capable
of expressing all possible starting positions of Chess960. However, unmodified
FEN cannot express all possible positions of a Chess960 game. In a game,
a rook may move into the back row on the same side of the king as the
other rook, or pawn(s) may be underpromoted into rook(s) and moved into
the back row. If a rook is unmoved and can still castle, yet there is
more than one rook on that side, FEN notation as traditionally interpreted
is ambiguous. This is because FEN records that castling is possible on
that side, but not which rook is still allowed to castle. A modification
of FEN, FRC-FEN, has been devised to remove this ambiguity. In FRC-FEN,
the castling markings "KQkq" have their expected meanings: "Q" and "q"
means A-side castling is still legal (for white and black respectively),
and "K" and "k" means H-side castling is still legal (for white and black
respectively). However, if there is more than one rook on the baseline
on the same side of the king, and the rook that can castle is not the
outermost rook on that side, then the column letter of the rook that can
castle is appended right after the related "K", "k", "Q", or "q". In other
words, in FRC-FEN notation, castling potentials belong to the outermost
rooks by default. This means that the maximum length of the castling value
is 8 characters instead of 4 (KkQq plus 4 disambiguation characters),
though positions needing that many characters are extremely improbable.