Quick answer
King Activity in Endgames is an endgame technique: king-and-pawn geometry. Work from the first evidence position for King Activity in Endgames, and begin by testing d5.
Begin from d5 in 8/8/8/8/3Pk3/8/8/2K5 w - - 2 2. Count the material, king routes, promotion squares and reserve tempi before applying a theoretical rule. The evidence answer is: King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5.
In the King Activity in Endgames example, notice: side White; pieces White pawn d4, Black king e4, White king c1; legal first moves d5, Kb2, Kc2, Kd2, Kd1, Kb1. Do not export this inventory beyond the present example; it is a local observation, not a doctrine.
Material and result question
The first evidence board tests king-and-pawn geometry; the second board tests king-and-pawn geometry. For the pair of examples, install A from direct FEN setup and install B from direct FEN setup. Hub vocabulary: Chess Wiki · Endgames hub. Then compare Material Values with Bishop Pawn And King, Pawn Endgame Calculation, Converting An Extra Pawn around the side-to-move tempo.
The two inventories make the distinction concrete. A contains side White; pieces White pawn d4, Black king e4, White king c1; legal first moves d5, Kb2, Kc2, Kd2, Kd1, Kb1; B contains side White; pieces Black king d6, White pawn d4, White king e3; legal first moves d5, Ke4, Kf4, Kf3, Kf2, Ke2, Kd2, Kd3. Compare the side to move before comparing the labels in the context of a reserve pawn move.
Topic dossier for this page and board pair r1:8 | r2:8 | r3:8 | r4:8 | r5:3Pk3 | r6:8 | r7:8 | r8:2K5 / r1:8 | r2:8 | r3:3k4 | r4:8 | r5:3P4 | r6:4K3 | r7:8 | r8:8: start with the side-to-move tempo; then test a reserve pawn move; keep the active rook before the pawn push separate from the conversion move order; use an outside passer used as a decoy as the transfer check; and reserve the defender's only active counterplay for the exception.
Conversion or defense plan
On the first board, calculate d5 after d5 and write down the opponent's best reply around the side-to-move tempo. On the second board, calculate d5 after d5 and check a reserve pawn move. Separate the practical conversion question from the result question; side to move and one checking distance can change the conclusion. In this case the useful condition is the defender's only active counterplay.
Key claim: King Activity in Endgames is illustrated here by king-and-pawn geometry; the first concrete test is d5. The board anchor is 8/8/8/8/3Pk3/8/8/2K5; the example is intentionally narrower than the topic label and should not be generalised without checking the surrounding position..
Practical boundary: To answer “What exact king, pawn, and move-order conditions decide king activity in endgames, and how should each side play them?”, compare the recorded setup with d5 and the opponent's reply. The decision is useful only when the stated condition survives that concrete test on board 8/8/3k4/8/3P4/4K3/8/8. The evidence records No tablebase outcome is asserted by this generated record; verify the exact FEN before publication and the second board signature r1:8 | r2:8 | r3:3k4 | r4:8 | r5:3P4 | r6:4K3 | r7:8 | r8:8. The false-positive test is whether the active rook before the pawn push appears without the conversion move order, so the conclusion is useful only when the stated condition survives that concrete test.
Evidence positions
example-1: king-and-pawn geometry
Show answer
King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5.
Why this position is here: King Activity in Endgames is represented by king-and-pawn geometry. This is a direct FEN setup with board anchor 8/8/8/8/3Pk3/8/8/2K5; no opening history is inferred from the diagram.
FEN: 8/8/8/8/3Pk3/8/8/2K5 w - - 2 2
Question: What is the first concrete decision in this king activity in endgames position?
Answer cue: King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5. The first candidate to test is d5. Replay d5 on board anchor 8/8/8/8/3Pk3/8/8/2K5 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
example-2: king-and-pawn geometry
Show answer
King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5.
Why this position is here: King Activity in Endgames is represented by king-and-pawn geometry. This is a direct FEN setup with board anchor 8/8/3k4/8/3P4/4K3/8/8; no opening history is inferred from the diagram.
FEN: 8/8/3k4/8/3P4/4K3/8/8 w - - 2 2
Question: What is the first concrete decision in this king activity in endgames position?
Answer cue: King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5. The first candidate to test is d5. Replay d5 on board anchor 8/8/3k4/8/3P4/4K3/8/8 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
example-3: king-and-pawn geometry
Show answer
King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5.
Why this position is here: King Activity in Endgames is represented by king-and-pawn geometry. This is a direct FEN setup with board anchor 8/8/8/8/3P4/4k3/8/5K2; no opening history is inferred from the diagram.
FEN: 8/8/8/8/3P4/4k3/8/5K2 w - - 4 3
Question: What is the first concrete decision in this king activity in endgames position?
Answer cue: King Activity in Endgames: count the king moves, the pawn's promotion square and the reserve tempo before pushing. Candidate line: d5. The first candidate to test is d5. Replay d5 on board anchor 8/8/8/8/3P4/4k3/8/5K2 and write down what changes after it.
Evidence boundary: No tablebase outcome is asserted by this generated record; verify the exact FEN before publication.
Reading the line
Read the first example (id example-1) as a complete record: continuation d5, source tablebase. This is a direct FEN setup with board anchor 8/8/8/8/3Pk3/8/8/2K5; no opening history is inferred from the diagram. If A does not expose king-and-pawn geometry, correct the evidence before relying on the prose.
Read the second example (id example-2) separately: continuation d5, source tablebase. Its feature is king-and-pawn geometry; inventory side White; pieces Black king d6, White pawn d4, White king e3; legal first moves d5, Ke4, Kf4, Kf3, Kf2, Ke2, Kd2, Kd3. Compare what changes between d5 and d5.
Boundary cases
The main mistake to avoid with King Activity in Endgames is applying a remembered endgame rule while ignoring side to move, king placement or an unverified result. In A, the missing condition must be located in r1:8 | r2:8 | r3:8 | r4:8 | r5:3Pk3 | r6:8 | r7:8 | r8:2K5 after d5; in B, test it against r1:8 | r2:8 | r3:3k4 | r4:8 | r5:3P4 | r6:4K3 | r7:8 | r8:8 after d5.
For King Activity in Endgames, the first board's evidence boundary (after d5) is No tablebase outcome is asserted by this generated record; verify the exact FEN before publication. The second board's evidence boundary for King Activity in Endgames is No tablebase outcome is asserted by this generated record; verify the exact FEN before publication. If a trusted source or careful calculation changes the conclusion around an outside passer used as a decoy, update both the evidence record and this article.
Practice from a real game
play the position for both sides, record the critical tempo, and verify the exact FEN against the cited tablebase before publication. Start with A's side to move and r1:8 | r2:8 | r3:8 | r4:8 | r5:3Pk3 | r6:8 | r7:8 | r8:2K5; record two candidates, the reply to d5 and the correction. Repeat with B's side to move and r1:8 | r2:8 | r3:3k4 | r4:8 | r5:3P4 | r6:4K3 | r7:8 | r8:8; the changed board tests transfer rather than diagram memory.
After the drill, compare your notes with Bishop Pawn And King, Pawn Endgame Calculation, Converting An Extra Pawn through the conversion move order. Keep A's rejected alternative beside B's chosen line d5; this shows whether the conclusion survived a new board signature.
Sources and scope
Sources for King Activity in Endgames: Syzygy tablebase verification reference, 1chess.online editorial scope. Source ids are tablebase, original-analysis. Primary evidence hook: tablebase. Comparisons and practice notes are editorial. Evidence revision: 2026-08-remediation-r2.
Scope note for board pair r1:8 | r2:8 | r3:8 | r4:8 | r5:3Pk3 | r6:8 | r7:8 | r8:2K5 / r1:8 | r2:8 | r3:3k4 | r4:8 | r5:3P4 | r6:4K3 | r7:8 | r8:8: this page does not claim that d5 is an engine principal variation, that an exact endgame result is verified when the evidence says it is not, or that a tool output replaces human calculation. The conclusion is limited to the recorded boundary and the exception the active rook before the pawn push.