King and Pawn vs King
King and pawn versus king is the endgame every other endgame secretly depends on: with one exception, White wins exactly when the attacking king can reach one of the pawn's key squares, and the fight for those squares is decided by the opposition. Master three ideas — key squares, the opposition, and the king-in-front rule — plus the rook-pawn exception, and you will evaluate any position of this type in seconds, which means you will also know which piece trades to allow and which to refuse for the rest of your chess life.
I tell my students that this is the multiplication table of chess. Nobody reaches this exact position often, but every simplification — every rook trade in a rook and pawn vs rook ending, every queen swap — must be checked against it before you make it. Strong players do not calculate these positions at the board; they read them.
Key Squares: The Test That Decides the Endgame
Every pawn owns a set of key squares: squares with the property that if the attacking king reaches any of them, the pawn promotes by force, no matter whose move it is and no matter where the defending king stands. For a pawn on e5, the key squares are d6, e6, and f6 — one rank ahead, all three files. Here is what it looks like when White already occupies one. White: king e6, pawn e5. Black: king e8. White to move.
1.Kd6! The one move to know: step diagonally past the pawn (1.Kf6 mirrors it; the careless 1.Kd5? or 1.Kf5? lets Black keep the opposition and draw). After 1...Kd8 2.e6 Ke8 3.e7 — no check, and that matters, as we will see — 3...Kf7 4.Kd7 and the pawn queens next move. Notice White never needed to calculate: king on the sixth rank in front of the pawn is a win with either side to move. That sentence alone wins games.
For pawns that have not yet crossed the middle of the board, the key squares sit two ranks ahead: a pawn on e4 has key squares d6, e6, f6 as well. From the fifth rank on, they move one rank ahead of the pawn, and everything accelerates.
The Opposition: How the Kings Fight for Those Squares
When the attacking king has not yet reached a key square, the defender's king plants itself in the way, and the duel is decided by the opposition — the standoff in which the king that must move is the one that loses ground. I will not re-derive the theory here; the glossary entry covers it. What you must see is how brutally it cashes out. White: king e5, pawn e4. Black: king e7. The kings face off with one square between them. If White is to move, the position is a dead draw — 1.Kd5 Kd7! 2.e5 Ke7 3.e6 Ke8! and Black keeps stepping in front. If Black is to move, White wins by force. Same pieces, same squares, opposite result.
After 1...Kd7, the winning move is 2.Kf6! — not the natural 2.Kd5?, which walks into the drawn face-off we just discussed with White, fatally, the one to move. White outflanks instead: 2...Ke8 3.Ke6 (opposition again, at closer range) 3...Kd8 4.Kf7. That last move is the point of the whole maneuver: the king now controls e8, the promotion square, and the pawn simply walks: 4...Kd7 5.e5 Kc6 6.e6 Kd6 7.e7 Kd7 8.e8=Q, protected by the king on f7. Every winning plan in this endgame is a version of this: use the opposition to force the defender aside, outflank, occupy a key square, and only then push.
The King Goes First — Even From the Starting Blocks
The most common practical error I see is pushing the pawn early. It feels active; it is usually the drawing move. Watch the correct technique from maximum distance. White: king e1, pawn e2. Black: king e8. This is a forced win — but only two first moves win, 1.Kd2 and 1.Kf2. Advancing the pawn first with 1.e3? or 1.e4? throws the full point away on move one, because the pawn burns the reserve tempo the king will need later.
1.Kd2 Kd7 2.Kd3 Kd6 3.Ke4 Ke6 — Black has the opposition, and without a resource White would be stuck. 4.e3! The pawn move changes whose turn it is to blink: now Black must give way, 4...Kd6 5.Kf5, and White outflanks exactly as before. That quiet 4.e3 is a spare tempo, the single most important weapon in pawn endings, and it exists only because White did not touch the pawn earlier. Rule of thumb worth engraving: king in front of the pawn, pawn as far back as possible.
The Rook-Pawn Exception
Everything above fails on the a- and h-files. A rook pawn has no "other side": the defending king cannot be outflanked because there is no file beyond the edge to outflank toward. If the defender's king reaches the corner — or even the squares in front of the pawn — the game is drawn no matter how perfectly White plays. Here White has the dream setup, king in front of the pawn on the sixth, and it still yields nothing.
1.Kb6 Ka8 2.a6 Kb8 3.a7+ Ka8 and White faces the cruel arithmetic of the corner: 4.Kc7 is stalemate, and any other king move drops the pawn. With a central pawn, the king would have escaped to the far side; here the far side does not exist. The full map of these draws — including the defender who camps in front of the pawn and the wrong-bishop cousin — lives in rook-pawn endings. For now, one trade-decision rule: an extra a- or h-pawn is worth far less than any other extra pawn, so steer your simplifications accordingly.
Reading the Position Before You Trade
Here is how this knowledge actually gets used. You are up a pawn in a queen ending, or your opponent offers a rook trade in a four-pawn ending that will liquidate to a single passed pawn. Before agreeing, you run the checklist, in order: Is it a rook pawn with the defending king near the corner? Draw — refuse. Can my king reach a key square before the defending king blocks it? Count it with the same care you apply the square rule to a running pawn. If the kings will land in a face-off, who ends up with the opposition — and do I have a spare pawn tempo to flip it? Those three questions settle nearly every K+P vs K position without calculation.
And they scale. Add a pawn for the attacker and you get king and two pawns vs king, where the second pawn mostly exists to donate tempi. Give the defender a pawn and you get king and pawn vs king and pawn, where both kings juggle attack and defense at once. Every one of those richer endgames is played by reducing it, in your head, to the position on this page — which is why I make every student master this one to the point of boredom before touching anything else. The general laws that grow out of it are collected in pawn endgame principles.
Frequently Asked Questions
Is king and pawn versus king always a win?
No. It is a win only if the attacking king can reach one of the pawn's key squares, which usually requires having the opposition at the critical moment. With correct defense, many positions are drawn — and with a rook pawn, the defender draws whenever the king reaches the corner in time, however well the attacker plays.
What are the key squares of a pawn?
For a pawn on its second, third, or fourth rank, the three squares two ranks ahead of it (d6, e6, f6 for an e4-pawn). From the fifth rank onward, the three squares directly one rank ahead. If the attacking king occupies any of them, the pawn promotes by force regardless of whose move it is.
Why should the king go in front of the pawn?
Because the king clears the path and wins the fight for the key squares, while the pawn's unspent moves serve as reserve tempi to flip the opposition. A pawn pushed ahead of its own king can usually be blockaded by the defending king forever, and the tempo it wasted is often exactly the one that would have won the opposition battle.
Why is the rook pawn a draw?
Outflanking needs space on both sides of the pawn, and at the edge of the board one side is missing. The defender who reaches the corner cannot be evicted: the attacker's tries end in stalemate or in losing the pawn, which is why king in front on the sixth wins with every pawn except the a- and h-pawns.
Who moves first matters that much?
In the critical face-off positions, yes — the identical arrangement of three pieces is a win with one side to move and a draw with the other. That is why strong players hoard spare pawn moves: a tempo in reserve lets you hand the "wrong" turn to the opponent at the decisive moment.