Caro-Kann Defense: what to play after d4?

In the Caro-Kann Defense (ECO B12), Black's established and overwhelming choice on move two is d5. By striking immediately at White's central e4 pawn, Black fulfills the core premise of the opening while maintaining a solid pawn structure. Engine analysis rates d5 as the strongest continuation at +0.43, and the move appears in 87.0% of recorded games (4.33 million recorded).

Strategic Purpose of the Main Line

The pawn push d5 challenges White's spatial supremacy and contests the d4 and e4 squares directly. Supported by the pawn on c6, Black ensures a stable anchor in the center without blocking the light-squared bishop. An illustrative continuation shows d5 e5 Bf5 Nf3 e6 Be2, where Black comfortably develops the c8 outside the pawn chain before locking the center with e6.

Alternative Second-Move Setups

Although vastly less common, Black occasionally tests alternative setups. The moves d6 (5.6% of games, 280K recorded, eval +0.72) and g6 (1.3% of games, 66K recorded, eval +0.73) steer play toward Pirc or Modern Defense structures, with an engine continuation running g6 c4 d6 Nc3 Nf6 Be2. Rare sidelines include Nf6, seen in 0.5% of games (26K recorded), as well as a6 (+0.58) and e6 (+0.76), both of which delay central confrontation and give White a freer hand in development.