Exercise 1.1Mate in 1
White to move
Checkmate in one move.
1
Calculation in Chess · Yatish Chandra Shukla
What Is Calculation?
Moving the pieces in your head
In this lesson you will learn
- What calculation really means, and why it matters
- The three questions to ask before every move
- How to tell whether a piece is really “free” — by counting
- How to take every reply of your opponent into account
Every board on this page is live. Move the pieces by tapping or dragging, click any move in the lines to see that position, and press ↺ to start again.
1.1 Playing the Moves in Your Head
Before you cross a road, you look both ways. You think: “How far away is that car? Where will it be by the time I'm halfway across?” You haven't stepped onto the road yet, but in your mind you have already crossed it. In chess, this is called calculation.
Calculation means: without touching the pieces, playing a few moves ahead in your head — your moves and your opponent's — and then deciding who will be better off at the end.
Many beginners play a move and then hope their opponent won't notice anything. This is jokingly called “hope chess.” If your opponent slips, you win; if not, you lose. Calculation turns that hope into a sure count.
NoteCalculation does not mean seeing very far ahead. At the start, seeing two or three moves correctly is plenty. Two correct moves are worth far more than ten wrong ones.
1.2 Three Questions Before Every Move
Where should calculation begin? Make a habit of asking these three questions before each of your moves:
- What does my opponent want? What did their last move change? Which checks, captures and threats do they have now?
- What moves do I have? Look first at the moves that force a reply — checks, captures and threats. These are called forcing moves.
- After my move, what is their best reply? Before you put your move on the board, sit in your opponent's chair in your mind.
Of the three, the third question is the one most often forgotten. In the next example, forgetting it is fatal.
Diagram 1.1White to move
Example 1 · The Greedy Pawn Grab
Black is a pawn up. White's eye falls on the pawn on b7: 1.♕xb7 — the pawn comes back and the material is level! The move looks easy. But before playing it, ask the third question: what does Black have after this?
Before reading on: what should White play?
Look at Black's checks. 1...♕e1+! and now White has only one move: 2.♖xe1 ♖xe1# — checkmate! White's king is trapped behind its own three pawns (f2, g2, h2), and no piece is guarding the first rank.
In fact this threat was already there — asking the first question (“What does my opponent want?”) would have revealed it. The right move is 1.h3! (or 1.g3), giving the king an escape square. Now after 1...♕e1+ 2.♖xe1 ♖xe1+ 3.♔h2 Black has given up a queen for a rook. White can take the b7 pawn on the next move.
LessonBefore grabbing anything for free, ask: what checks does my opponent have? A king stuck on the back rank behind its pawns is always a warning sign.
1.3 Is That Piece Really Free?
When several pieces from both sides are aimed at the same square, a chain of captures can follow. Here guesswork won't do — you need to count. First, remember the value of the pieces:
Pawn1
Knight3
Bishop3
Rook5
Queen9
Before capturing on any square:
- Count how many pieces attack the square and how many defend it.
- If attackers outnumber defenders, the capture is usually fine; if they are equal or fewer, be careful.
- Numbers alone aren't enough — look at value too. It is better to capture with the cheaper piece first.
- The surest method: play the whole sequence in your head and add up the score at the end — who gave what, and who got what.
Diagram 1.2White to move
Example 2 · The Knight on e4
Black's knight sits in the centre on e4. Can White win it?
Attackers: ♘c3 and ♗d3 — two. Defenders: the d5 pawn and ♗f5 — two. The numbers are equal, so the knight is not free. But an exchange is possible: 1.♘xe4 dxe4 — knight for knight, a fair trade.
Now there is a black pawn on e4. Only ♗d3 attacks it and only ♗f5 defends it — one against one. If White greedily plays 2.♗xe4?? then 2...♗xe4 — White has given a 3-point bishop for a 1-point pawn. Correct is 2.♗c2 or 2.♗e2, and the e4 pawn will remain a weakness.
LessonCheck a sequence one capture at a time. The first capture may be fine and the second a blunder. Count again after every capture.
1.4 Look at Every Reply
When calculating, we often think only of the reply we would like. But your opponent will look for their best reply. So after a forcing move, list all of your opponent's possible answers — after a check there are usually only two or three.
Diagram 1.3White to move
Example 3 · 1.♗xh7+ — two replies
White wants to play 1.♗xh7+. What happens next?
After the check Black has only two moves (the rook stands on f8). Look at each one separately.
A — 1...♔xh7 2.♘g5+! is check to the king and an attack on the queen on e6 at the same time. The king moves, then 3.♘xe6. White wins the queen.
B — 1...♔h8! Now the king attacks the bishop on h7, so 2.♗d3 brings it back. White is a pawn up.
If you had looked only at line A, you would think you had won the queen. In reality a good player will choose 1...♔h8, and you get just a pawn. 1.♗xh7+ is still a good move — your expectations just need to be correct.
LessonWhen you calculate, assume your opponent plays their best move, not their worst. After a check, list every reply — the list is short, and that makes calculation easy.
1.5 More Examples
Study each example as if it were a puzzle: solve it on the board first, then read the solution.
Diagram 1.4Black to move
Example 1.4
Black to move. Is anything free? Count the attackers and defenders before you capture.
Find the key move for Black.
1...♖xd7 — the queen on d7 was not defended. Black wins the queen and keeps a winning position. White's other defences do not help. Compare the natural alternative 1...♔a8?: after it White is clearly better. That is far less than the key move achieves.
LessonA piece without a defender is the easiest target on the board. Before every move, ask which pieces are loose — yours and your opponent's.
Diagram 1.5Black to move
Example 1.5
Black to move. Is anything free? Count the attackers and defenders before you capture.
Find the key move for Black.
1...♕xd2 — the bishop on d2 was not defended. Black wins a bishop for a pawn and keeps a winning position. White's other defences do not help. Compare the natural alternative 1...♕xe1+?: after it Black is a little better. That is far less than the key move achieves.
LessonLook for squares from which one piece attacks two targets at the same time — especially with check.
Diagram 1.6Black to move
Example 1.6
Black to move. Is anything free? Count the attackers and defenders before you capture.
Find the key move for Black.
1...♗xa6 — the queen on a6 was not defended. Black wins the queen. White's other defences do not help. Compare the natural alternative 1...♘g3?: after it White is clearly better. That is far less than the key move achieves.
LessonA piece without a defender is the easiest target on the board. Before every move, ask which pieces are loose — yours and your opponent's.
Diagram 1.7Black to move
Example 1.7
Black to move. Is anything free? Count the attackers and defenders before you capture.
Find the key move for Black.
1...axb5 — the bishop on b5 was not defended. Black wins a bishop. White's other defences do not help. Compare the natural alternative 1...c4?: after it the position is about equal. That is far less than the key move achieves.
LessonA piece without a defender is the easiest target on the board. Before every move, ask which pieces are loose — yours and your opponent's.
Remember
- Calculation = playing a few moves ahead in your head, without touching the pieces.
- Three questions before every move: What does my opponent want? What do I have? After my move, what is their best reply?
- Look at forcing moves first — checks, captures, threats — both yours and theirs.
- Before capturing, count attackers and defenders, then add up the values.
- After a check, examine every possible reply of your opponent separately.
Daily practiceIn your next ten games, before every move ask yourself: “After this, which checks does my opponent have?” The game will feel slow at first, but within a few days the question will start to come up on its own.
Exercises · Lesson 1
Spend at least three minutes on each puzzle. Work out the full line in your head — not just your first move, but your opponent's replies too — then play your answer on the board. Open the hint only if you are stuck for a long time.
Exercise 1.2Question
Black to move
Black wants to win a pawn with 1...♘xd4. Is this a good idea?
Is 1...♘xd4 a good idea?
Exercise 1.3Find the move
White to move
White is far behind — Black has a queen. Find one move that turns the game around.
Exercise 1.4Mate in 2
White to move
Checkmate in two moves.
Exercise 1.5Question
Black to move
1.e4 e5 2.♘f3 d6 3.♗c4 ♗g4 4.♘c3 g6? 5.♘xe5! — White's queen on d1 looks free. Should Black play 5...♗xd1?
Should Black take the queen with 5...♗xd1?
Exercise 1.6Find the move
White to move
Black's d5 pawn is isolated. Can White win it? Count to find out.
Exercise 1.7Mate in 1
White to move
Checkmate in one move.
Exercise 1.8Mate in 1
Black to move
Checkmate in one move.
Exercise 1.9Mate in 1
White to move
Checkmate in one move.
Exercise 1.10Mate in 1
White to move
Checkmate in one move.
Exercise 1.11Find the move
Black to move
Black to move. Is anything free? Win material.
Exercise 1.12Find the move
White to move
White to move. Is anything free? Win material.
Exercise 1.13Find the move
White to move
White to move. Is anything free? Win material.
Exercise 1.14Find the move
Black to move
Black to move. Is anything free? Win material.
Exercise 1.15Find the move
White to move
White to move. Is anything free? Win material.
Exercise 1.16Find the move
Black to move
Black to move. Is anything free? Win material.
Exercise 1.17Find the move
Black to move
Black to move. Is anything free? Win material.
Exercise 1.18Find the move
White to move
White to move. Is anything free? Win material.
Exercise 1.19Find the move
Black to move
Black to move. Is anything free? Win material.
Exercise 1.20Find the move
Black to move
Black to move. Is anything free? Win material.