How to checkmate with rook and king
The one that actually costs beginners half points. A rook cannot do it alone, and knowing that is most of the technique.
- Worst case, perfect play: 16 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 rook on an open rank or file draws a line the enemy king cannot cross. That is the whole of the ending. The king is left in a box, and the box gets one rank smaller at a time until it is a single square on the edge of the board.
The part that is not obvious is that the rook cannot make the box smaller on its own. Once the line is drawn, the enemy king simply stands behind it and waits, and no rook move takes anything away. The only thing that can make it move is your king walking up and standing opposite it. The rook draws the line; the king does the pushing. Almost every failed rook ending is a player checking with the rook and leaving the king at home.
The method
- Draw the line. Put the rook on a rank or file between the two kings. Now the enemy king is on one side of it and has half the board or less.
- Walk your king in. Straight at the enemy king. Nothing else is happening on the board and there is nothing else to do.
- Take the opposition. Get your king directly facing the enemy king with exactly one square between them, on the same rank or file. Now the enemy king cannot come towards you and cannot stay where it is if it is your opponent to move.
- Push. If the enemy king steps sideways, follow it with your king. If it steps back, move the rook forward one line and start again -- the box just got a rank smaller.
- If the kings face each other and it is your move, waste one. Slide the rook along its line, away from the enemy king. Now it is their move and they must give ground. This is the move nobody finds on their own.
- Mate. Enemy king on the edge, your king directly opposite it, rook checks along the edge. There is nowhere to go.
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 42 and the mate is played when it is one. It does not fall smoothly: four of White's 13 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. In a rook ending the box opens whenever the rook steps off the line it was cutting on, and closes again one rank nearer when it lands. Played by the method, that gap lasts one move and the floor keeps dropping.
Show the whole line
| White | Box | Black | Box | |
|---|---|---|---|---|
| 1. | Kf3 | 32 | Kc4 | 32 |
| 2. | Rd2 | 26 | Kc3 | 26 |
| 3. | Rd5 | 34 | Kb4 | 34 |
| 4. | Ke3 | 34 | Kc4 | 34 |
| 5. | Re5 | 23 | Kb3 | 23 |
| 6. | Kd3 | 10 | Kb4 | 10 |
| 7. | Rd5 | 23 | Kb3 | 23 |
| 8. | Rd4 | 18 | Kb2 | 18 |
| 9. | Rb4+ | 45 | Ka3 | 32 |
| 10. | Kc3 | 3 | Ka2 | 3 |
| 11. | Kc2 | 32 | Ka3 | 32 |
| 12. | Rc4 | 3 | Ka2 | 3 |
| 13. | Ra4# | 1 | — | — |
Replayed through the same rules engine the app runs on. The final
position is called checkmate because isCheckmate() says it is.
What goes wrong
- Leaving your king at home. The most common failure by a distance. If your king has not moved in five moves, the technique is not running.
- Checking for the sake of it. A check that pushes the king sideways along its own rank has achieved nothing. In the trainer, watch the box count: a check that does not shrink it was a wasted move.
- Letting the king chase the rook. When the enemy king attacks the rook, slide it to the far end of the same line. The line is still drawn and the rook is now three squares out of reach.
- Forgetting there is a clock. The worst case with perfect play is 16 moves and you have fifty. That sounds generous until you spend twenty of them shuffling.
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: 16 moves with perfect play on both sides from the least convenient starting position there is. That is a third of your allowance, so there is room for imperfect technique. There is not room for twenty moves of aimless checking first.
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 30 for this ending -- 14 more than perfect play would need.
How to checkmate with rook and king, for real Free, no sign-up, works offline. It warns you before you stalemate and explains it if you do. Practise rook and kingQuestions people ask
How do you checkmate with just a king and rook?
Cut the enemy king off with the rook, walk your own king up until it stands directly opposite the enemy king with one square between them, and then push. Every time the enemy king gives ground, move the rook one line further forward and cut it off again. Mate comes when the king is on the edge, your king is facing it, and the rook checks along the edge.
Why can't the rook do it on its own?
Because a rook can draw a line but cannot take away the squares behind it. Once the enemy king is standing behind the line, no rook move makes the space any smaller -- the king just moves along its own rank. Only your king standing opposite it can force it backwards. That is what the opposition is for.
What is the fastest king and rook checkmate?
It depends entirely on where the pieces start. Working backwards from every checkmate position that exists, the longest a perfectly defending king can survive from the worst position for it is 16 moves, and most positions are considerably shorter than that. Anything under twenty is sound technique.
Can you stalemate with a rook?
Yes, and it is easy to do on the edge: a king on the eighth rank with your rook on the seventh and your king not yet opposite it can be left with no legal move and no check. The habit is the same as with a queen -- count the enemy king's squares before every quiet move.
Where can I practise king and rook checkmate?
On this page. The trainer generates a fresh position every time, the defending king takes anything you hang and refuses to step into mate in one, and it tells you when your move is about to stalemate it.
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
- Queen and kingQuickest to learn, easiest to draw by accident
- 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.