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Blackmar-Diemer Gambit Declined: O'Kelly Defense

258K games from Lichess · Updated January 2026

Tough Sell
Black Expected Score45.1%Range (90% confident): 44.9% – 45.2%Based on 258K games
0%45.1%100%
Range (90% confident): 44.9% – 45.2%
Outcome Distribution
43.3%3.5%53.2%
Win
Draw
Loss
4...c6
Blackmar-Diemer Gambit Declined: O'Kelly Defense
Analyzen=258K
Avg Length32 moves
Sharpness97%
Draw Rate3.5%

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense expected score for Black?

Snapshot

At all ratings, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 45.1% expected score for Black (we're 90% confident it's between 44.9% and 45.2%), based on 258K Lichess games.

Black Win% by Rating

Declines with rating: 45% → 42%

0
1000
1200
1400
1600
1800
2000
2200
2500+

  • 0-999: 44.8% win rate (4,783 games)
  • 1000-1199: 43.9% win rate (6,799 games)
  • 1200-1399: 43.4% win rate (11,645 games)
  • 1400-1599: 42.8% win rate (20,984 games)
  • 1600-1799: 43.2% win rate (36,228 games)
  • 1800-1999: 43.0% win rate (59,782 games)
  • 2000-2199: 43.6% win rate (65,959 games)
  • 2200-2499: 43.3% win rate (44,764 games)
  • 2500+: 41.5% win rate (7,185 games)

Black Win% by Time Control

Best in UltraBullet (48%), worst in Rapid (43%)

UltraBullet
Bullet
Blitz
Rapid
Classical

  • UltraBullet: 48.4% win rate (1,184 games)
  • Bullet: 43.2% win rate (139,692 games)
  • Blitz: 43.3% win rate (96,283 games)
  • Rapid: 43.1% win rate (20,385 games)
  • Classical: 45.4% win rate (585 games)

Black% by Rating × Time Control

Click any cell to filter. Green = above 50%, Red = below 50%.

RatingUBBulleBlitzRapidClass
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, UltraBullet: 70.0% expected score (1 games)
  • 0-999 rating, Bullet: 47.7% expected score (944 games)
  • 0-999 rating, Blitz: 46.0% expected score (2,341 games)
  • 0-999 rating, Rapid: 47.9% expected score (1,491 games)
  • 0-999 rating, Classical: 63.4% expected score (6 games)
  • 1000-1199 rating, UltraBullet: 52.5% expected score (19 games)
  • 1000-1199 rating, Bullet: 45.3% expected score (2,095 games)
  • 1000-1199 rating, Blitz: 45.4% expected score (2,944 games)
  • 1000-1199 rating, Rapid: 46.0% expected score (1,691 games)
  • 1000-1199 rating, Classical: 54.9% expected score (50 games)
  • 1200-1399 rating, UltraBullet: 43.1% expected score (42 games)
  • 1200-1399 rating, Bullet: 45.7% expected score (4,658 games)
  • 1200-1399 rating, Blitz: 42.7% expected score (4,862 games)
  • 1200-1399 rating, Rapid: 47.2% expected score (2,021 games)
  • 1200-1399 rating, Classical: 44.5% expected score (62 games)
  • 1400-1599 rating, UltraBullet: 55.9% expected score (209 games)
  • 1400-1599 rating, Bullet: 43.4% expected score (7,838 games)
  • 1400-1599 rating, Blitz: 44.3% expected score (9,974 games)
  • 1400-1599 rating, Rapid: 44.4% expected score (2,846 games)
  • 1400-1599 rating, Classical: 53.8% expected score (117 games)
  • 1600-1799 rating, UltraBullet: 47.7% expected score (600 games)
  • 1600-1799 rating, Bullet: 44.3% expected score (14,222 games)
  • 1600-1799 rating, Blitz: 44.9% expected score (16,875 games)
  • 1600-1799 rating, Rapid: 45.1% expected score (4,390 games)
  • 1600-1799 rating, Classical: 46.2% expected score (141 games)
  • 1800-1999 rating, UltraBullet: 50.0% expected score (156 games)
  • 1800-1999 rating, Bullet: 44.3% expected score (26,555 games)
  • 1800-1999 rating, Blitz: 44.9% expected score (28,157 games)
  • 1800-1999 rating, Rapid: 44.9% expected score (4,756 games)
  • 1800-1999 rating, Classical: 42.2% expected score (158 games)
  • 2000-2199 rating, UltraBullet: 48.6% expected score (108 games)
  • 2000-2199 rating, Bullet: 44.8% expected score (39,360 games)
  • 2000-2199 rating, Blitz: 46.8% expected score (23,806 games)
  • 2000-2199 rating, Rapid: 44.6% expected score (2,636 games)
  • 2000-2199 rating, Classical: 53.0% expected score (49 games)
  • 2200-2499 rating, UltraBullet: 39.1% expected score (44 games)
  • 2200-2499 rating, Bullet: 45.2% expected score (37,100 games)
  • 2200-2499 rating, Blitz: 47.4% expected score (7,067 games)
  • 2200-2499 rating, Rapid: 47.3% expected score (551 games)
  • 2200-2499 rating, Classical: 21.5% expected score (2 games)
  • 2500+ rating, UltraBullet: 11.5% expected score (5 games)
  • 2500+ rating, Bullet: 44.5% expected score (6,920 games)
  • 2500+ rating, Blitz: 42.7% expected score (257 games)
  • 2500+ rating, Rapid: 38.9% expected score (3 games)

Related Openings

Variations (5)
Blackmar-Diemer Gambit Declined: Vienna Defense
49.4%
Blackmar-Diemer Gambit Declined: Weinsbach Defense
55.1%
Blackmar-Diemer Gambit Declined: Lamb Defense
47.6%
Blackmar-Diemer Gambit Declined: Langeheinicke Defense
49.4%
Blackmar-Diemer Gambit Declined: Elbert Countergambit
47.7%
Analyze Blackmar-Diemer Gambit Declined: O'Kelly Defense PositionsGet move-by-move win rates with the TrueElo analyzer

Frequently Asked Questions

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate?

The Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 53.2% (90% CI: 53.0%-53.4%) win rate for white, based on 258K rated games from Lichess.

At what rating does the Blackmar-Diemer Gambit Declined: O'Kelly Defense perform best?

The Blackmar-Diemer Gambit Declined: O'Kelly Defense performs best at 1400-1599 Elo with a 54.6% win rate for white (21K games). Win rate tends to decline at higher ratings as opponents know the theory better.

Is the Blackmar-Diemer Gambit Declined: O'Kelly Defense better in blitz or rapid?

Bullet (53.9%) outperforms Classical (49.9%) by 4.0%. Choose your time control wisely.

How sharp is the Blackmar-Diemer Gambit Declined: O'Kelly Defense?

The Blackmar-Diemer Gambit Declined: O'Kelly Defense has a sharpness score of 96.5 (very decisive), meaning 96.5% of games end decisively. Average game length is 32 moves.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 0-999 Elo?

At 0-999 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 50.9% (90% CI: 49.7%-52.1%) win rate for white, based on 4.8K Lichess games. Average game length is 28 moves with a 4.3% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 1000-1199 Elo?

At 1000-1199 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 52.7% (90% CI: 51.7%-53.7%) win rate for white, based on 6.8K Lichess games. Average game length is 29 moves with a 3.4% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 1200-1399 Elo?

At 1200-1399 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 54.0% (90% CI: 53.3%-54.8%) win rate for white, based on 12K Lichess games. Average game length is 28 moves with a 2.6% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 1400-1599 Elo?

At 1400-1599 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 54.6% (90% CI: 54.0%-55.1%) win rate for white, based on 21K Lichess games. Average game length is 29 moves with a 2.6% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 1600-1799 Elo?

At 1600-1799 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 53.8% (90% CI: 53.3%-54.2%) win rate for white, based on 36K Lichess games. Average game length is 30 moves with a 3.1% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 1800-1999 Elo?

At 1800-1999 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 53.8% (90% CI: 53.4%-54.1%) win rate for white, based on 60K Lichess games. Average game length is 32 moves with a 3.2% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 2000-2199 Elo?

At 2000-2199 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 52.7% (90% CI: 52.3%-53.0%) win rate for white, based on 66K Lichess games. Average game length is 33 moves with a 3.7% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 2200-2499 Elo?

At 2200-2499 Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 52.3% (90% CI: 52.0%-52.7%) win rate for white, based on 45K Lichess games. Average game length is 35 moves with a 4.3% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate at 2500+ Elo?

At 2500+ Elo, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 52.8% (90% CI: 51.8%-53.8%) win rate for white, based on 7.2K Lichess games. Average game length is 40 moves with a 5.7% draw rate.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate in UltraBullet?

In UltraBullet games, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 50.5% (90% CI: 48.1%-52.9%) win rate for white (1.2K Lichess games). Draw rate is 1.1%.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate in Bullet?

In Bullet games, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 53.9% (90% CI: 53.6%-54.1%) win rate for white (140K Lichess games). Draw rate is 2.9%.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate in Blitz?

In Blitz games, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 52.5% (90% CI: 52.2%-52.8%) win rate for white (96K Lichess games). Draw rate is 4.2%.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate in Rapid?

In Rapid games, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 52.3% (90% CI: 51.7%-52.9%) win rate for white (20K Lichess games). Draw rate is 4.6%.

What is the Blackmar-Diemer Gambit Declined: O'Kelly Defense win rate in Classical?

In Classical games, the Blackmar-Diemer Gambit Declined: O'Kelly Defense has a 49.9% (90% CI: 46.5%-53.3%) win rate for white (585 Lichess games). Draw rate is 4.7%.

Is the Blackmar-Diemer Gambit Declined: O'Kelly Defense a good opening?

The Blackmar-Diemer Gambit Declined: O'Kelly Defense is statistically favors white with a 53.2% (90% CI: 53.0%-53.4%) win rate across all ratings. It performs best at 1400-1599 Elo. Your results depend on your rating, time control, and how well you know the typical plans.