Chessy
Play the King's Gambit Accepted: Bishop's Gambit, Kieseritzky Gambit as Black
The King's Gambit is one of the most aggressive openings in chess. After 1.e4 e5 2.f4 exf4, White can immediately develop the bishop to a dangerous diagonal with 3.Bc4. As Black, you face a critical decision — and the most dynamic answer is 3...b5, sacrificing a pawn to undermine White's bishop and launch a counterattack. This is the Kieseritzky Gambit, and it leads to sharp, unbalanced play where you are the one chasing the king. Stockfish rates the position at +0.04, meaning it's dead level — neither side is better out of the opening. Below you can test yourself against the engine and learn the key ideas.
Play the King's Gambit Accepted: Bishop's Gambit, Kieseritzky Gambit against the engine
Free, no signup — you play black, the engine adapts to your level.
Test yourself in the interactive drill below — play the Kieseritzky Gambit as Black against an adapting engine and see if you can punish White's mistakes. Sign'
Create a free account →The Point of 3...b5: Counterattack Before Defence
Many Black players instinctively defend against the bishop's threat, but the Kieseritzky Gambit says: attack first. The move 3...b5 attacks the bishop on c4, forcing it to move or capture. If White takes the pawn — which the engine says is best — you follow up with 4...c6, attacking the bishop again and gaining time. Your ultimate idea is 5...Qh4+, putting White's king under immediate fire. You willingly give up a pawn (the one on b5) to seize the initiative, and the statistics confirm the plan is sound. Over 715 games from this position, Black wins 41.5% of the time — a fantastic result for a gambit where you are down material. White wins 56.4%, and only 2.1% of games end in a draw, meaning the opening almost always produces a decisive outcome.
White's Best Move and Your Response
The engine recommends 4.Bxb5, accepting the pawn sacrifice. Across 433 Lichess games, White scores 54.0% with this move — still strong, but it gives you the most counterplay. After 4.Bxb5, you play 4...c6, attacking the bishop a second time. White's safest retreat is 5.Ba4, after which you strike with 5...Qh4+. This queen check is the heart of the gambit: White's king is stuck in the centre and cannot castle kingside. You are trading a pawn for rapid development and a direct attack. Even though the position is theoretically equal, the practical pressure is on White to find precise moves. Many club players panic under the check and blunder.
Which White Moves Are Traps (and Which Are Gifts)
If your opponent does not know the theory, they might try to avoid taking on b5. The statistics show these alternative moves punish White, not you. Here are the three common mistakes for White in this position, all worse than Bxb5:
Punishing White's Mistakes
- 4.Bb3 (197 games, White scores 64.0%) — This is an inaccuracy that loses about 0.8 pawns of advantage. By retreating to b3, White avoids the pawn grab but leaves you with a healthy extra pawn on f4 and no immediate threats. You should simply keep the pawn and develop naturally, with moves like ...Nf6 and ...d5 to come. The engine says White should have taken on b5 instead. — 4.Bxf7+ (54 games, White scores 55.6%) — This is a mistake costing White about 1.1 pawns. If White takes on f7, you recapture with ...Kxf7. White wins a pawn but loses the powerful light-squared bishop, and your king is actually safe for now. You have a comfortable position with two bishops and an extra pawn. — 4.Bd5 (19 games, White scores 47.4%) — This is also a mistake, losing about 1.2 pawns. After 4.Bd5, you can push ...c6 immediately, attacking the bishop with tempo. White's bishop has no safe square and must retreat, losing time. You come out ahead in development with an extra pawn. If you face any of these moves, you are already doing better than the statistics suggest — make sure to punish White's inaccuracy by keeping your extra pawn and activating your pieces. The engine's best move is always 4.Bxb5, so if White plays anything else, you have a tangible advantage.
Results across 715 Lichess games
| Most-played continuation | Games | White wins |
|---|---|---|
| Bxb5 | 433 | 54.0% |
| Bb3 | 197 | 64.0% |
| Bxf7+ | 54 | 55.6% |
| Bd5 | 19 | 47.4% |
| Nf3 | 5 | 40.0% |
| d4 | 2 | 50.0% |
Frequently asked questions
Is the Kieseritzky Gambit sound for Black?
Yes, it is completely sound at the club level. Stockfish rates the position after 3...b5 at +0.04, which is dead equal. You sacrifice a pawn but gain a powerful attack with ...Qh4+ that puts White's king under immediate pressure. In practice, Black scores 41.5% from this position, which is excellent for a gambit.
What is the best response to 3...b5 in the King's Gambit?
The engine's best move for White is 4.Bxb5, accepting the pawn sacrifice. After that, you play 4...c6, attacking the bishop again. White typically retreats with 5.Ba4, and then you deliver the check 5...Qh4+. This sequence gives you active piece play and a lead in development.
What happens if White plays 4.Bb3 instead of taking the pawn?
If White plays 4.Bb3, it is an inaccuracy that loses about 0.8 pawns of theoretical advantage. White avoids the complications of the gambit but leaves you with an extra pawn on f4. You should keep the pawn, develop your pieces, and play for a comfortable middlegame. Statistically, White still scores 64.0% with this move in practice, so stay alert.
Is 4.Bxf7+ a good move for White?
No, 4.Bxf7+ is a mistake that loses about 1.1 pawns. After you recapture with ...Kxf7, White has won a pawn but lost the powerful light-squared bishop. Your king is safe enough, and you have the bishop pair plus an extra pawn. White's attacking chances are greatly reduced without the bishop.