Petrov's Defense
Chess opening · ECO C42 · 4 half-moves
1. e4 e5 2. Nf3 Nf6
The Petrov's Defense is reached after 1. e4 e5 2. Nf3 Nf6. It is White's move in the position shown.
It branches from the King's Knight Opening with 2… Nf6.
How often it is played
The Petrov's Defense and its variations appeared in 1.3% of games — 37,825 of 3,000,000 rated games sampled from Lichess in September 2026. That makes it number 41 of the openings listed here.
Results
White won 50%, 3.9% were drawn and Black won 46%. These are games between players of every strength and time control, so they say how the opening does in practice rather than how sound it is.
What the engine thinks
Stockfish, at depth 18, evaluates the position at +0.46 — a small edge for White. Positive numbers favour White; see reading the evaluation bar.
Similar openings
The most-played alternatives — what else could have been chosen around the move where this opening begins.
| Opening | Moves | Share of games |
|---|---|---|
| King's Knight Opening: Normal Variation | 1. e4 e5 2. Nf3 Nc6 | 10% |
| Philidor Defense | 1. e4 e5 2. Nf3 d6 | 2.1% |
| King's Pawn Game: Busch-Gass Gambit | 1. e4 e5 2. Nf3 Bc5 | 0.39% |
Main continuations
| Variation | Moves | Share of games |
|---|---|---|
| Petrov's Defense: Three Knights Game | 1. e4 e5 2. Nf3 Nf6 3. Nc3 | 0.34% |
| Petrov's Defense: Italian Variation | 1. e4 e5 2. Nf3 Nf6 3. Bc4 | 0.27% |
| Petrov's Defense: Stafford Gambit | 1. e4 e5 2. Nf3 Nf6 3. Nxe5 Nc6 | 0.13% |
| Petrov's Defense: Modern Attack | 1. e4 e5 2. Nf3 Nf6 3. d4 | 0.12% |
| Petrov's Defense: Damiano Variation | 1. e4 e5 2. Nf3 Nf6 3. Nxe5 Nxe4 | 0.07% |
| Petrov's Defense: Classical Attack | 1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. d4 | 0.03% |
| Petrov's Defense: Cozio Attack | 1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. Qe2 | 0.02% |
| Petrov's Defense: Nimzowitsch Attack | 1. e4 e5 2. Nf3 Nf6 3. Nxe5 d6 4. Nf3 Nxe4 5. Nc3 | 0.01% |
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