Quick answer
Clearance Sacrifice is a tactical idea: a sacrifice that removes a king defender. Work from the first evidence position for Clearance Sacrifice, and begin by testing Kh8.
Begin from Kh8 in 6k1/5ppp/8/8/8/5N2/B4PPP/6K1 b - - 1 1. Start with the forcing geometry: checks, captures, threats, defenders and flight squares around the target. The evidence answer is: Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Kh8.
In the Clearance Sacrifice example, notice: side Black; pieces Black king g8, Black pawn f7, Black pawn g7, Black pawn h7, White knight f3, White bishop a2, White pawn f2, White pawn g2, White pawn h2, White king g1; legal first moves Kh8, Kf8, g6, g5, h6, h5. Do not export this inventory beyond the present example; it is a local observation, not a doctrine.
The tactical trigger
The first evidence board tests a sacrifice that removes a king defender; the second board tests a sacrifice that removes a king defender. For the pair of examples, install A from direct FEN setup and install B from direct FEN setup. Hub vocabulary: Chess Wiki · Tactics hub. Then compare Candidate Moves with Anastasia S Mate, Clearance Move, Interference around a quiet threat after the forcing move.
The two inventories make the distinction concrete. A contains side Black; pieces Black king g8, Black pawn f7, Black pawn g7, Black pawn h7, White knight f3, White bishop a2, White pawn f2, White pawn g2, White pawn h2, White king g1; legal first moves Kh8, Kf8, g6, g5, h6, h5; B contains side White; pieces Black king h8, Black pawn h7, Black pawn f5, Black pawn g5, White bishop c4, White pawn f2, White pawn g2, White pawn h2, White knight e1, White king g1; legal first moves Bb5, Ba6, Bd5, Be6, Bf7, Bg8, Bd3, Be2. Compare the side to move before comparing the labels in the context of an in-between move before recapture.
Topic dossier for this page and board pair r1:6k1 | r2:5ppp | r3:8 | r4:8 | r5:8 | r6:5N2 | r7:B4PPP | r8:6K1 / r1:7k | r2:7p | r3:8 | r4:5pp1 | r5:2B5 | r6:8 | r7:5PPP | r8:4N1K1: start with a quiet threat after the forcing move; then test an in-between move before recapture; keep the defender carrying two jobs separate from the line revealed after clearance; use the order of checks before captures as the transfer check; and reserve the loose unit behind the target for the exception.
Calculation order
On the first board, calculate Kh8 after Kh8 and write down the opponent's best reply around a quiet threat after the forcing move. On the second board, calculate Bb5 after Bb5 and check an in-between move before recapture. Calculate the most forcing move first, then test the opponent's best capture, interposition or counter-check before naming the motif. In this case the useful condition is the loose unit behind the target.
Key claim: Clearance Sacrifice is illustrated here by a sacrifice that removes a king defender; the first concrete test is Kh8. The board anchor is 6k1/5ppp/8/8/8/5N2/B4PPP/6K1; the example is intentionally narrower than the topic label and should not be generalised without checking the surrounding position..
Practical boundary: To answer “How can a player recognize clearance sacrifice, calculate the winning idea, and test the defender's best resource?”, compare the recorded setup with Bb5 and the opponent's reply. The decision is useful only when the stated condition survives that concrete test on board 7k/7p/8/5pp1/2B5/8/5PPP/4N1K1. The evidence records Illustrative evidence for the stated mechanism; it is not a claim that the candidate move is forced or best in every position and the second board signature r1:7k | r2:7p | r3:8 | r4:5pp1 | r5:2B5 | r6:8 | r7:5PPP | r8:4N1K1. The false-positive test is whether the defender carrying two jobs appears without the line revealed after clearance, so the conclusion is useful only when the stated condition survives that concrete test.
Evidence positions
example-1: a sacrifice that removes a king defender
Show answer
Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Kh8.
Why this position is here: Clearance Sacrifice is represented by a sacrifice that removes a king defender. This is a direct FEN setup with board anchor 6k1/5ppp/8/8/8/5N2/B4PPP/6K1; no opening history is inferred from the diagram.
FEN: 6k1/5ppp/8/8/8/5N2/B4PPP/6K1 b - - 1 1
Question: What is the first concrete decision in this clearance sacrifice position?
Answer cue: Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Kh8. The first candidate to test is Kh8. Replay Kh8 on board anchor 6k1/5ppp/8/8/8/5N2/B4PPP/6K1 and write down what changes after it.
Evidence boundary: Illustrative evidence for the stated mechanism; it is not a claim that the candidate move is forced or best in every position.
example-2: a sacrifice that removes a king defender
Show answer
Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Bb5.
Why this position is here: Clearance Sacrifice is represented by a sacrifice that removes a king defender. This is a direct FEN setup with board anchor 7k/7p/8/5pp1/2B5/8/5PPP/4N1K1; no opening history is inferred from the diagram.
FEN: 7k/7p/8/5pp1/2B5/8/5PPP/4N1K1 w - - 0 4
Question: What is the first concrete decision in this clearance sacrifice position?
Answer cue: Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Bb5. The first candidate to test is Bb5. Replay Bb5 on board anchor 7k/7p/8/5pp1/2B5/8/5PPP/4N1K1 and write down what changes after it.
Evidence boundary: Illustrative evidence for the stated mechanism; it is not a claim that the candidate move is forced or best in every position.
example-3: a sacrifice that removes a king defender
Show answer
Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Bxf7.
Why this position is here: Clearance Sacrifice is represented by a sacrifice that removes a king defender. This is a direct FEN setup with board anchor 7k/5pp1/8/7p/8/8/B4PPP/4N1K1; no opening history is inferred from the diagram.
FEN: 7k/5pp1/8/7p/8/8/B4PPP/4N1K1 w - - 2 3
Question: What is the first concrete decision in this clearance sacrifice position?
Answer cue: Clearance Sacrifice: calculate the forcing continuation and compare the material cost with the king exposure. Candidate line: Bxf7. The first candidate to test is Bxf7. Replay Bxf7 on board anchor 7k/5pp1/8/7p/8/8/B4PPP/4N1K1 and write down what changes after it.
Evidence boundary: Illustrative evidence for the stated mechanism; it is not a claim that the candidate move is forced or best in every position.
Reading the line
Read the first example (id example-1) as a complete record: continuation Kh8, source fide-laws. This is a direct FEN setup with board anchor 6k1/5ppp/8/8/8/5N2/B4PPP/6K1; no opening history is inferred from the diagram. If A does not expose a sacrifice that removes a king defender, correct the evidence before relying on the prose.
Read the second example (id example-2) separately: continuation Bb5, source fide-laws. Its feature is a sacrifice that removes a king defender; inventory side White; pieces Black king h8, Black pawn h7, Black pawn f5, Black pawn g5, White bishop c4, White pawn f2, White pawn g2, White pawn h2, White knight e1, White king g1; legal first moves Bb5, Ba6, Bd5, Be6, Bf7, Bg8, Bd3, Be2. Compare what changes between Kh8 and Bb5.
The defensive resource
The main mistake to avoid with Clearance Sacrifice is spotting a familiar motif but failing to test the defender's strongest legal resource. In A, the missing condition must be located in r1:6k1 | r2:5ppp | r3:8 | r4:8 | r5:8 | r6:5N2 | r7:B4PPP | r8:6K1 after Kh8; in B, test it against r1:7k | r2:7p | r3:8 | r4:5pp1 | r5:2B5 | r6:8 | r7:5PPP | r8:4N1K1 after Bb5.
For Clearance Sacrifice, the first board's evidence boundary (after Kh8) is Illustrative evidence for the stated mechanism; it is not a claim that the candidate move is forced or best in every position. The second board's evidence boundary for Clearance Sacrifice is Illustrative evidence for the stated mechanism; it is not a claim that the candidate move is forced or best in every position. If a trusted source or careful calculation changes the conclusion around the order of checks before captures, update both the evidence record and this article.
Practice from a real game
cover the answer, list checks and captures, and record the defender or escape square that decides whether the idea works. Start with A's side to move and r1:6k1 | r2:5ppp | r3:8 | r4:8 | r5:8 | r6:5N2 | r7:B4PPP | r8:6K1; record two candidates, the reply to Kh8 and the correction. Repeat with B's side to move and r1:7k | r2:7p | r3:8 | r4:5pp1 | r5:2B5 | r6:8 | r7:5PPP | r8:4N1K1; the changed board tests transfer rather than diagram memory.
After the drill, compare your notes with Anastasia S Mate, Clearance Move, Interference through the line revealed after clearance. Keep A's rejected alternative beside B's chosen line Bb5; this shows whether the conclusion survived a new board signature.
Sources and scope
Sources for Clearance Sacrifice: 1chess.online editorial scope, FIDE Laws of Chess. Source ids are original-analysis, fide-laws. Primary evidence hook: fide-laws. Comparisons and practice notes are editorial. Evidence revision: 2026-08-remediation-r2.
Scope note for board pair r1:6k1 | r2:5ppp | r3:8 | r4:8 | r5:8 | r6:5N2 | r7:B4PPP | r8:6K1 / r1:7k | r2:7p | r3:8 | r4:5pp1 | r5:2B5 | r6:8 | r7:5PPP | r8:4N1K1: this page does not claim that Kh8 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 defender carrying two jobs.