Lesson No.008

ECO C42 White wins Opening: Intermediate Medium game, 37 moves Opening: Petrov's Defense

Black

hgfe dcba

8765 4321

1234 5678

abcd efgh

White

Explanation

Game Moves

Show best moves

#	White	Best	Black	Best
1	e4	e4	e5	c5
2	Nf3	Nf3	Nf6	Nc6
3	Nxe5	Nxe5	Nc6	d6
4	Nxc6	Nxc6	dxc6	dxc6
5	d3	d3	h6	Bc5
6	c3	Be2	Be6	Bg4
7	Qc2	Be2	Qd7	c5
8	d4	Be2	O-O-O	g5
9	Nd2	Be2	Kb8	Re8
10	Be2	Be2	g5	g5
11	O-O	O-O	g4	h5
12	b4	f4	h5	h5
13	Nb3	f4	b6	Re8
14	c4	c4	Bxb4	h4
15	a3	d5	Nxe4	Be7
16	axb4	axb4	h4	Nxf2
17	Bd3	Bf4	f5	Nxf2
18	Qa2	Qa2	a5	Qg7
19	Nxa5	Nxa5	c5	Nc3
20	b5	Bxe4	Bd5	Qg7
21	Nc6+	cxd5	Bxc6	Bxc6
22	Qa7+	bxc6	Kc8	Kc8
23	bxc6	bxc6	Qxc6	Qxc6
24	d5	d5	Kd7	Qb7
25	dxc6+	dxc6+	Kxc6	Kxc6
26	Bf4	Qa4+	Rd6	Nd6
27	Qa4+	Qa4+	Kb7	Kb7
28	Qa7+	Qa6+	Kc8	Kc8
29	Bxe4	Bxe4	fxe4	fxe4
30	Bxd6	Bxd6	Rh7	cxd6
31	Qa8+	Rfd1	Kd7	Kd7
32	Rfd1	Rfd1	g3	Rg7
33	Bf8+	Bxc5+	Ke6	Ke6
34	Qc6+	Qc6+	Kf7	Kf7
35	Rd7+	Rd7+	Kg8	Kg8
36	Qg6+	Qg6+	Rg7	Rg7
37	Qxg7#	Qxg7#

Detailed Analysis

Evaluation Chart

Evaluation: How good the position is, in pawns (1 pawn = 1.0). + (blue) means you are better, − (red) means your opponent is. Capped at ±10. Touch a point to see the actual value.

◆ Mate: A position with checkmate in sight (shown at ±10). Touch a point to see the moves to checkmate (M3: you mate in 3, -M3: your opponent mates in 3).

Skill Radar

Estimated from engine evaluations. It may not match your actual strength.

How Scores Work: For each move, the winning chance (calculated from the evaluation) before and after the move is compared; the less it drops, the higher the move's accuracy. Each item is the average accuracy of its moves (out of 100). Items with fewer than 3 moves show (-) (Tactics is scored from a single move).

Opening	Moves 1 to 10
Tactics	Moves right after the opponent dropped their winning chance by 10% or more (did you take the chance?)
Strategy	Moves other than Opening, Endgame and Tactics
Endgame	Moves once both sides together have 8 or fewer pieces other than kings and pawns
Consistency	Share of all moves that did not drop the winning chance by 10% or more

* The win % and accuracy formulas are based on Lichess's calculations.

Win % and Accuracy

Win %: Your chance of winning (0–100), calculated from the evaluation after each move.

Accuracy: For each of your moves, a score (0–100) comparing your winning chance before and after the move. A move that keeps your winning chance scores 100.