Opening

English Defense

At 1400–1799 Elo, theory ends around half-move 10. The move that leaves it is a mistake in 10% of cases, 4.8 times as often as a move inside it.

All openings

Where theory ends

Half-move at which a game leaves what at least 100 games played. Half of all games end between the two outer numbers.

up to 1399
9
half-move
half of the games: 7 to 11
1400–1799
10
half-move
half of the games: 8 to 12
1800+
11
half-move
half of the games: 9 to 13

How risky the exit is

Share of moves that lose at least 10 points of winning chances, in the same stretch of the game (half-moves 8 to 24).

up to 1399

Inside theory2.5%
The move that leaves it13.9%
After it16.2%

5.5× the risk of a move inside theory

1400–1799

Inside theory2.1%
The move that leaves it10.3%
After it11.8%

4.8× the risk of a move inside theory

1800+

Inside theory1.6%
The move that leaves it8.3%
After it8.7%

5.1× the risk of a move inside theory

Most common mistakes inside theory

Moves the engine rates down although many players choose them. The last move of each line is the mistake, the loss is the mean in points of winning chances.

1. d4 b6 2. f4798 played, 10.1 points lost
1. d4 b6 2. c4 Bb7 3. Nc3 Nf6 4. e4719 played, 11.8 points lost
1. d4 b6 2. c4 Bb7 3. Nc3 Nc6718 played, 13.1 points lost
1. d4 b6 2. e3 Bb7 3. Bd3690 played, 31.1 points lost
1. d4 b6 2. c4 Bb7 3. Nc3 d5635 played, 10.1 points lost
1. d4 b6 2. Nf3 Bb7 3. Nc3 Bxf3551 played, 10 points lost

Where does your theory end?

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More openings

Opening names from the Lichess opening database (CC0). A game belongs to the most specific named opening it reaches within 39 half-moves.