Czech Defense
B07 1. e4 d6 2. d4 Nf6 3. Nc3 c6
White scores 48.7% here across 436 club games — but the 29.8% who answer Nf3 score 43.5%, 5 points worse.
What White actually plays here
Across 436 games from a Lichess-derived book of club play, White scores 48.7% in this position. These are the replies people choose, and how each one works out.
| Reply | Games | Share | White scores | Verdict |
|---|---|---|---|---|
| Nf3 | 130 | 29.8% | 43.5% | below the line |
| f4 | 72 | 16.5% | 52.1% | holds up |
| Bg5 | 62 | 14.2% | 45.2% | below the line |
| Bd3 | 38 | 8.7% | 43.4% | below the line |
| Be3 | 33 | 7.6% | 43.9% | below the line |
| h3 | 27 | 6.2% | 55.6% | holds up |
"Below the line" means the reply scores at least three points worse than the position does overall. Replies played fewer than 25 times are left out: the sample is too small to read.
Is this costing you anything?
A table of averages cannot tell you whether you go wrong here — only your own games can. Opening Leak Lab reads your Chess.com or Lichess archive, finds the decisions you repeat, and checks each one against this book and a bundled Stockfish.