Learning the moves of all the pieces is one thing, but a beginner chess player will quickly discover that to actually checkmate the opponent’s king is a surprisingly difficult task. In fact, without a few guidelines on how to checkmate your opponent it will be almost impossible to achieve. In this lesson you will learn a few fundamental checkmate patterns that will enable you to execute a checkmate on your opponent’s king.
Below the video is a transcript (with diagrams).
How to checkmate your opponent’s king
In this lesson you will learn the meaning of three important words in chess: check, checkmate and stalemate. When you make a move that attacks your opponent’s king, then we say the king is in check. And when a king is in check, the king must do something to get out of check. It is a rule in chess – a king may not stay in check, and if he is in check, then he must do something to get out of check. There are a few ways to get out of check.
I’ll use this example to show you the different ways a king can get out of check:

Here black moves their rook and attacks the white king. It’s check. There are 3 possible ways to get out of check.
The first way is to, if you can, capture the piece that checks your king.

So, if you capture the black rook with your bishop, then your king wouldn’t be in check anymore. The second way to get out of check is to block the piece that checks your king. For example, you could place your rook here to block and now your king isn’t in check anymore.

Of course, if he captures your rook and says check again, then you can recapture him and this would be an equal exchange.

The third way to get out of check is to simply move your king to a safe square where nothing can capture him.

Which option would you choose in this case? Would you capture the rook or would you block the check or would you move your king?

Well, you should of course capture the rook because you are winning 5 points. I want to repeat this important rule. If your king is in check, then you must do something to get him out of check. For example, in this case the king is not allowed to move here,

otherwise he will be in check by black’s bishop. Even if white makes this move accidentally, then he must take back that move and move somewhere else where his king won’t be in check. But now, what happens when a king is in check and there is nothing he can do to get out of check? Let me show you what I mean:
White moves their rook and checks the black king:

And now there is nothing black can do to get the king out of check, because wherever he goes – he will be in check with one of white’s rooks. If this happens (a king is in check and there is nothing he can do to get out of check), that is checkmate. If you checkmate your opponent’s king, then you win the game. So now you know the difference between check and checkmate. The third important word you must now know, is the word stalemate.
I’ll show you an example to illustrate what stalemate is.

White move their queen to g6 and now it’s black’s turn. But, black can’t move. There is nowhere the king can go. It’s almost like checkmate, but the difference is – the king isn’t actually in check. When this happens, when a player absolutely cannot make any moves, and their king isn’t in check, then that is what we call stalemate. That means – nobody wins, and the game ends in a draw.
Notice that if black had another piece, for example if he had a knight here…

then he would not be in stalemate. This is because even though the king can’t move, he would still be able to make a move with the knight. It’s only stalemate if there is absolutely nothing a player can move and he also isn’t in check.
Let me show you a few more examples to illustrate the difference between check, checkmate and stalemate. Here’s the first one:

White moves their queen and checks the black king. But, the king is not in checkmate because even though he can’t move anywhere, he could simply capture the queen and then wouldn’t be in check anymore. The next example is slightly different:

White again moves the queen to check black’s king and in this case the king can’t move anywhere, but he also can’t capture the queen, otherwise he will be in check by the bishop. In this case, black’s king is in checkmate.
Here it’s white’s turn to move, but white can’t move.

Anywhere the king wants to go he would be in check either by black’s rook or black’s bishop. So, the king can’t move at all. But the pawns can’t move either since they are blocked. So even though white can’t move here, he isn’t in check, which means this is stalemate and the game ends in a draw. Nobody wins.
There’s a few important ways to checkmate your opponent’s king. The first one I will show you, is how to checkmate their king when you have two rooks and your opponent has only their king.
We start here. How can you get the black king into checkmate?

Well, first of all, you should understand that it’s pointless to simply keep on checking their king, because he will simply keep running away and you won’t be making any progress. The trick is to trap their king to one of the sides of the board. And this is how you do it.
White moves their rook here…

because now he covers all these squares and it means the king isn’t able to move further away from the side anymore, because he is not allowed to move into check. He can go left or right but let’s say he goes here:

White moves the other rook and checks the black king:

And in this case, it is not just a pointless check, because you are in fact forcing their king to move closer to the side of the board. The king can’t go down, because the white rooks cover all these squares.
Let’s say black goes here, closer to the side:

White now check’s him again with this rook, forcing black to go to the side of the board:

And that is why we didn’t move this rook…

because if we did, then the black king would again be able to move further away from the side which isn’t what we want to happen. Instead we check with the other rook.

And now black’s king is forced to move to the side, but black has one last trick up his sleeve. He moves here,

and now white must be careful because if he moves the rook here to check the king, then black could simply capture him. So, what should white do?
Well, he can simply move the rook here…

because now black’s king will be forced to move away, and once he goes here…

we can check him with either of the rooks:

And now it’s checkmate because there is nothing black can do to get out of check. So, this is how you would checkmate someone if you had two rooks and they had only a king. You use the two rooks to force the enemy king to the side of the board and then you checkmate them there.
Next, I’ll show you how to checkmate an opponent when you have a king and a queen, whilst they have only a king. I’ll use this position as a starting point:

You should already know that it would be pointless to keep on checking the black king because they will simply move out of check every time and you wouldn’t be making much progress. So again, you must first find a way to try force their king to the side of the board where he can’t run freely. I’ll show you how to do that. The trick is that you use your queen to trap the enemy king in a cage. And then you keep making the cage smaller until their king is trapped on the side of the board.
White moves the queen to c4… can you see the cage?

The black king can never move outside the cage. Black must move. He can’t go to d5 as that would be check, so let’s say he goes to d6.

Of course, white must be careful the whole time. If he now moves the queen to c5, then the black king could capture her. Now instead of moving the queen, white brings their king closer to support the queen.

Black moves their king back to e5…

and now white can move the queen to d4…

which not only checks the black king, but also makes the cage a bit smaller. Of course, black can’t capture the queen in this case, otherwise he will be in check by white’s king. So, you can see the white king plays an important role here to support the queen.
The black king goes to f5 and white, again, makes the cage a bit smaller by moving the queen to e4.

Then, black’s king goes to g5 and white’s queen goes to f4..

The cage is getting even smaller.
Black goes to g6, and now white must again be careful not to play their queen to f5, otherwise the black king could capture her. Instead, white bring the king closer to help:

Black goes to g7 and white moves their queen to f5.

You can see the cage is getting very small now! Black moves their king to g8 and now there is two ways to make the cage smaller:

You could move your queen to f6 which would be good, or, you can simply move the queen to d7,

and this is a great move because now the black king is trapped right against the side of the board. Let’s say he goes to h8. White must again be careful here because if he moves the queen to f7…

it would be stalemate. It would be a draw and that is not what we want. Instead, white leaves the queen on d7 and brings their king closer to support the queen.

Black must move to g8 as it’s the only move. And white moves their king to g6.

Black has two options but both lead to checkmate. If he goes back to h8, then Qh7 would be checkmate. He can’t capture your queen as he will be in check. Or the other option black has… if he moves to f8…

then, similarly, white plays Qf7 and this would also be checkmate. This is how you should aim to checkmate your opponent’s king when you have a king and queen and they have only a king.
To conclude this lesson, I want to show you something interesting. What is the quickest possible checkmate in chess? It’s two moves, but it only works if the player with the white pieces make two bad moves at the start of the game.
It goes like this:

White moves their pawn to f3 and black moves their pawn to e5:
White now goes here…

which is a very bad move because now black moves their queen to h4 and says checkmate:

There is nothing white can do to get out of check. There is no way to capture the black queen right away, and the white king can’t move. If he goes to f2, it’s still check, and white can’t block either – the bishop only moves on diagonals and the knight also can’t help. White is in checkmate. Now I should say that chances are very slim that you would be able to get the opportunity to checkmate your opponent in this way but at least now you know what the quickest checkmate in chess looks like.
We’ve reached the end of this lesson and you’ve learned a few important ways you can use to checkmate your opponent’s king. In the next lesson we will take a look at a few special moves and special rules you need to know.
End of Lesson 3 – How to checkmate your opponent’s king