Facts & curiosities · 4 min read
9 interesting chess facts, with examples to explore
Some of the most interesting chess facts are easy to explore with a board in front of you. Others take us into the game’s history, from medieval pieces to early chess computers. This collection brings together nine fun facts about chess, with examples to try and sources if you’d like to read more.
The quick answer
White has 20 legal moves from the starting position, a knight changes square color with every move, and promotion can give you more than one queen. These are a few of the details you can explore below, alongside stories from chess history.
1. White has 20 legal first moves
You can count the legal moves on a starting board quite easily. Each of the eight pawns can advance one square or two, giving 16 pawn moves, and each knight has two available destinations, giving four knight moves. All the other pieces are blocked for now.
That adds up to 20 possible first moves. After any one of them, Black also has 20 replies, giving 400 possible sequences after one move by each side. The choices begin to depend on the position after that, so the total doesn’t keep growing by a simple factor of 20.
2. A knight changes square color with every move
A knight’s movement always takes it from a light square to a dark one, or from a dark square to a light one. You can see why by following its path: two squares in one direction bring it back to the same color, and the final sideways step changes the color.
Try the sequence below, starting with a knight on g1. Moving to f3, then g5, then e4 changes the color at every step. This also lets you predict the result of a longer journey: after an odd number of moves, the knight will be on the opposite color from where it began.
3. A bishop stays on one color for the whole game
A bishop moves diagonally, so it always stays on the color it started on. That means a light-squared bishop can visit only the 32 light squares, even if the rest of the board is empty.
Following a diagonal from c1 is an easy way to see this: every square along that line is dark. It also helps explain why players value having both bishops, since bishops on opposite colors can work across different parts of the board.
4. You can have more than one queen
When a pawn reaches the last rank, it can promote to a queen even if your original queen is still in play. You don’t have to choose a piece that has already been captured; FIDE’s promotion rules allow you to add another queen.
If all eight pawns promoted and the original queen survived, you could theoretically have nine queens. It’s an unusual possibility to think about, though in most games even one successful promotion makes a substantial difference.
5. Promotion gives you a choice of four pieces
A pawn can become a queen, rook, bishop, or knight. Choosing a piece other than a queen is called underpromotion, and there are positions where it’s the best choice.
A knight is particularly useful to consider because it attacks squares a queen on the same square wouldn’t reach. Promoting to a knight can sometimes create an immediate fork, while choosing a rook instead of a queen can avoid stalemate in certain positions. The right choice depends on what the new piece needs to do.
6. A pawn capture can end on an empty square
The en passant rule allows this unusual capture. When an opposing pawn advances two squares and lands beside yours, you may be able to capture it by moving onto the square it crossed. You then remove the opposing pawn from its neighboring square.
It can be surprising when you first see it, but it’s part of standard chess. Chess.com’s explanation covers the details, including the timing: you have to make the capture on the immediate reply.
7. Some medieval chessmen are shown biting their shields
Among the Lewis chessmen are warders holding their shields to their mouths. The British Museum’s account of the collection describes these distinctive figures, which are usually dated to around 1150–1200.
They’re a lovely example of how different a chess set can look from the pieces used in modern tournaments. The shapes and characters in a set tell us something about the people who made it, as well as the game itself. You can read more about those changes in our short history of chess.
8. Deep Blue beat Kasparov in a six-game match
In 1997, IBM’s Deep Blue defeated Garry Kasparov 3½–2½ over six games, becoming the first computer to win a match against a reigning world chess champion under standard tournament conditions.
There had been an earlier meeting in 1996, when Deep Blue won an individual game but Kasparov won the match. IBM’s history of Deep Blue describes both encounters, which together show how the computer developed between the two events.
9. Doubling grains across a chessboard gives a 20-digit total
Imagine putting one grain on the first square, two on the second, four on the third, and continuing to double the amount. Across all 64 squares, you would have 18,446,744,073,709,551,615 grains, or 2⁶⁴ − 1.
You can try the calculation with just four squares: 1 + 2 + 4 + 8 = 15. The same pattern carries on as the board fills. Our chess origins article includes a slider for exploring the grain-doubling story, along with the legend it comes from.
If you have a board nearby, try sharing one of these examples with someone you play with. Following a knight’s changing square color or counting the available first moves is a simple way to notice something new about a familiar game.
Sources & further reading
The diagrams and exercises are teaching examples. Rules references apply to standard chess unless stated otherwise.