King's Gambit Accepted: Kieseritzky, Polerio Defense
3.8K games from Lichess · Updated January 2026
Black expected score · All ratings · All speeds
50.4%
the worst score you would still get, 90% confident. At best 51.8%.
Measured over 3.8K games at this level and clock.
Roughly even — the middlegame decides more than this opening choice does.
Outcomes for Black
Draw 3.2 · Score = win + ½ of the draws · 3.8K games
- Rank among the families Black can choose here
- not ranked — this is a variation, not a family
- Games in this context
- 3.8K
- Best context
- 52.3% at 1600-1799 Blitz
- Worst context
- 51.6% at 1800-1999 Blitz
- Average game length
- 26 moves
- Games that end decisively
- 96.8%
- Draws
- 3.2%
Best and worst are the strongest and weakest squares with at least 500 games behind them. The table further down shows every square, including thinner ones.
Extra Analysis
Deep-dive datasets for this opening
Where it holds · Black score by rating × clock
Green is clearly ahead for Black, grey is around even, red is behind. Tap a cell to measure there, and again to clear. It gets better as the rating rises: 44.5% at 0-999, 55.5% at 2500+.
| Rating | UB | Bulle | Blitz | Rapid | Class |
|---|---|---|---|---|---|
| 0-999 | — | — | — | ||
| 1000-1199 | — | ||||
| 1200-1399 | — | — | |||
| 1400-1599 | — | ||||
| 1600-1799 | — | ||||
| 1800-1999 | — | ||||
| 2000-2199 | — | ||||
| 2200-2499 | — | — | |||
| 2500+ | — | — |
Expected score matrix by rating bracket and time control
- 0-999 rating, Bullet: 50.0% expected score (4 games)
- 0-999 rating, Blitz: 38.9% expected score (3 games)
- 1000-1199 rating, Bullet: 60.9% expected score (26 games)
- 1000-1199 rating, Blitz: 64.9% expected score (12 games)
- 1000-1199 rating, Rapid: 42.4% expected score (5 games)
- 1000-1199 rating, Classical: 30.0% expected score (1 games)
- 1200-1399 rating, Bullet: 50.0% expected score (36 games)
- 1200-1399 rating, Blitz: 47.4% expected score (56 games)
- 1200-1399 rating, Rapid: 56.5% expected score (14 games)
- 1400-1599 rating, Bullet: 53.2% expected score (110 games)
- 1400-1599 rating, Blitz: 47.5% expected score (178 games)
- 1400-1599 rating, Rapid: 57.2% expected score (40 games)
- 1400-1599 rating, Classical: 44.2% expected score (7 games)
- 1600-1799 rating, Bullet: 50.3% expected score (207 games)
- 1600-1799 rating, Blitz: 52.3% expected score (621 games)
- 1600-1799 rating, Rapid: 50.8% expected score (133 games)
- 1600-1799 rating, Classical: 64.3% expected score (9 games)
- 1800-1999 rating, Bullet: 50.0% expected score (235 games)
- 1800-1999 rating, Blitz: 51.6% expected score (854 games)
- 1800-1999 rating, Rapid: 51.8% expected score (226 games)
- 1800-1999 rating, Classical: 26.5% expected score (7 games)
- 2000-2199 rating, Bullet: 54.6% expected score (152 games)
- 2000-2199 rating, Blitz: 47.7% expected score (451 games)
- 2000-2199 rating, Rapid: 44.8% expected score (170 games)
- 2000-2199 rating, Classical: 16.7% expected score (3 games)
- 2200-2499 rating, Bullet: 41.0% expected score (65 games)
- 2200-2499 rating, Blitz: 48.2% expected score (110 games)
- 2200-2499 rating, Rapid: 48.5% expected score (31 games)
- 2500+ rating, Bullet: 73.1% expected score (5 games)
- 2500+ rating, Blitz: 63.4% expected score (6 games)
- 2500+ rating, Rapid: 30.0% expected score (1 games)
Related Openings
Methodology
Across every rating and clock, the King's Gambit Accepted: Kieseritzky, Polerio Defense scores 50.4% for Black — we are 90% confident the real figure is between 49.1% and 51.8% — from 3.8K Lichess games. Win rate, draw rate and loss rate come from games played December 2023 to November 2025.
How the figures are made
- Whose games these are
- 3.8K+ rated games played on Lichess (2023-12 to 2025-11). The games are Lichess’s and free for anyone to use. What is ours is the reading of them. Last rebuilt January 2026.
- Which games we count
- Rated games only — nothing casual.
- Both players within 200 rating points of each other. A mismatch tells you about the gap, not about the opening.
- At least 2 moves played.
- A game is filed under White’s rating.
- Why every number comes with a range
- A number off a few hundred games is a guess. The same number off millions is a fact. The range is what tells them apart, and it is what the lists rank on — so an opening cannot reach the top on a lucky run of forty games. The more games behind a figure, the narrower its range.
- How much we need before we say anything
- An opening page needs 100 games. A gambit needs 50 games at a rating before we will say whether it pays there. The chaos and trap lists need 500 games overall and 250 games at one rating or clock.
Frequently Asked Questions
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate?
Playing the King's Gambit Accepted: Kieseritzky, Polerio Defense, Black wins 48.8%, draws 3.2% and loses 48.0%. Counting a draw as half a point, that is an Expected Score of 50.4%. It rests on 3.8K rated games from Lichess.
At what rating does the King's Gambit Accepted: Kieseritzky, Polerio Defense perform best?
The King's Gambit Accepted: Kieseritzky, Polerio Defense performs best for Black at 1600-1799, with an Expected Score of 51.8% (970 games) and the highest Floor of any rating with enough games to read.
Is the King's Gambit Accepted: Kieseritzky, Polerio Defense better in blitz or rapid?
For Black, the King's Gambit Accepted: Kieseritzky, Polerio Defense scores about the same in both: an Expected Score of 50.5% in Blitz (2.3K games) against 49.8% in Rapid (620 games).
How sharp is the King's Gambit Accepted: Kieseritzky, Polerio Defense?
The King's Gambit Accepted: Kieseritzky, Polerio Defense has a sharpness score of 96.8 (very decisive), meaning 96.8% of games end decisively. Average game length is 26 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate at 1200-1399?
At 1200-1399, Black wins 48.8%, draws 1.4% and loses 49.8%. Counting a draw as half a point, that is an Expected Score of 49.5%. It rests on 106 Lichess games, which average 21 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate at 1400-1599?
At 1400-1599, Black wins 49.5%, draws 1.9% and loses 48.6%. Counting a draw as half a point, that is an Expected Score of 50.5%. It rests on 335 Lichess games, which average 21 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate at 1600-1799?
At 1600-1799, Black wins 50.2%, draws 3.1% and loses 46.7%. Counting a draw as half a point, that is an Expected Score of 51.8%. It rests on 970 Lichess games, which average 24 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate at 1800-1999?
At 1800-1999, Black wins 49.5%, draws 3.4% and loses 47.2%. Counting a draw as half a point, that is an Expected Score of 51.2%. It rests on 1.3K Lichess games, which average 28 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate at 2000-2199?
At 2000-2199, Black wins 46.1%, draws 4.2% and loses 49.7%. Counting a draw as half a point, that is an Expected Score of 48.2%. It rests on 776 Lichess games, which average 29 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate at 2200-2499?
At 2200-2499, Black wins 43.6%, draws 4.6% and loses 51.8%. Counting a draw as half a point, that is an Expected Score of 45.9%. It rests on 206 Lichess games, which average 31 moves.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate in Bullet?
In Bullet, Black wins 50.0%, draws 2.3% and loses 47.7%. Counting a draw as half a point, that is an Expected Score of 51.2%. It rests on 840 Lichess games.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate in Blitz?
In Blitz, Black wins 48.7%, draws 3.6% and loses 47.7%. Counting a draw as half a point, that is an Expected Score of 50.5%. It rests on 2.3K Lichess games.
What is the King's Gambit Accepted: Kieseritzky, Polerio Defense win rate in Rapid?
In Rapid, Black wins 48.2%, draws 3.1% and loses 48.7%. Counting a draw as half a point, that is an Expected Score of 49.8%. It rests on 620 Lichess games.
Is the King's Gambit Accepted: Kieseritzky, Polerio Defense a good opening?
The King's Gambit Accepted: Kieseritzky, Polerio Defense is about level. Across all ratings, Black wins 48.8% of its games and loses 48.0%. It performs best at 1600-1799. Your results depend on your rating, time control, and how well you know the typical plans.