How to checkmate with queen and king

Two or three moves of technique and one habit. The habit is the whole page, because the way this ending gets thrown away is not running out of moves -- it is stalemate.

• Worst case, perfect play: 10 moves
• You are allowed 50
• Every trainer position a proven forced win
• Free practice, no account

What the mate looks like

Start at the end. Every basic mate happens on an edge or in a corner, and it is worth knowing the finished picture before learning the moves that produce it.

The idea

A queen takes squares away faster than anything else on the board, which makes this the shortest of the basic mates: the worst case with perfect play is 10 moves. It also makes it the one people draw. Take away too many squares at the wrong moment and the enemy king has no legal move and is not in check, and a game you were winning by a queen is a draw.

So the technique here is not really about mating. It is about confining a king with a piece that is dangerously good at it.

The method

1. Put the queen a knight's move away from the enemy king. Not next to it. A knight's move -- two squares one way and one the other.
2. Every time the king moves, put the queen a knight's move away again. That is the entire first phase. The king has no choice but to be walked backwards towards an edge, and while the queen is a knight's move away it is impossible to stalemate, because the king always has the square it came from.
3. Stop when the king reaches the edge. This is the moment the method changes and the moment people lose the game. Do not move the queen again yet.
4. Walk your king up. Bring it to the square facing the enemy king with one square between them, or to any square that defends the mating square.
5. Mate. With your king in place, put the queen next to the enemy king on the edge -- your king defends it, the enemy king cannot take it, and every square is covered. Or check along the edge rank from a distance if your king covers the escape squares.

The stalemate that catches everybody

This is it. Not a puzzle, not a rare accident -- the natural confining move against a king in the corner, and the game is over.

One square. That is the entire margin between winning with a queen and drawing with one, and it is why the rule is worth making automatic: before a quiet move, count the enemy king's squares. If the answer is one, the move has to be a check. The trainer on the practice page counts them for you and says so before you can do it.

A worked example, move by move

The position on the right above, played out. This is not a line somebody typed in: it is the shortest forced mate that exists from that position, taken from a tablebase built for this page, with Black defending as well as it is possible to defend.

The box columns are the squares the black king could still walk to if White stood still. It starts at 23 and the mate is played when it is one. It does not fall smoothly: two of White's 7 moves here leave the king more room than it had, not less. That is real and it is worth understanding. A tablebase plays the shortest mate it can find rather than the most teachable one, and it can afford a move that opens the box because it can already see the finish. You cannot, which is why the method above trades a few moves for a box that mostly only shrinks. A queen changes the picture so much with a single move that the number jumps about more here than anywhere else. Watch the floor rather than the step.

What goes wrong

• The stalemate. The king is in a corner and you play the natural confining move; it takes away the last square, it is not a check, and the game ends. It is drawn out below because a picture of it is worth more than a warning about it.
• Bringing the queen next to the king too early. A queen next to a king with nothing defending it is simply taken.
• Forgetting your own king. The queen confines but cannot mate alone except along an edge, and even then the king usually has to cover something. Bring it before you need it.
• Chasing with checks. Every check that does not shrink the box has cost a move and increased the number of chances to stalemate.

How long you actually have

Fifty moves. Under the fifty-move rule a game is drawn on request once fifty moves pass with no capture and no pawn move, and in an ending like this one nothing is ever captured, so the count runs from the moment the last piece came off the board.

Working backwards from every checkmate position that exists with these pieces until every position has an exact answer gives the real worst case: 10 moves with perfect play on both sides from the least convenient starting position there is. You will almost never come close to it. The queen ending is not lost on the clock, it is lost to stalemate.

Practise it

Reading the method is the easy half. The trainer below the fold on the practice page gives you a fresh generated position, a defending king that does not help you, a live count of the box, and a move budget of 20 for this ending -- 10 more than perfect play would need.

Questions people ask

The other basic mates

Five endings, one page each, all of them forced wins.

• Two rooksThe ladder. The easiest of the five, and the place to start
• Rook and kingThe one that decides real games
• Two bishopsTwo pieces making a wall the king cannot cross
• Bishop and knightThe hard one, described honestly
• All five, and the trainerPractice, budgets and the box

Elsewhere on the site: endgame tactics from real games, mate in one for seeing a mate before forcing one, stalemate and the opposition in the glossary, and free printable worksheets for clubs and classrooms.