Chess Stalker — Free Chess Opponent Analysis

Analyze any Lichess, Chess.com or FIDE player's openings, weaknesses, blunder patterns and psychological profile. Train against a Twin Bot that replicates your opponent's style. Search by username or FIDE ID across 11 million+ games. Free to use, no signup required.

What you get

Opponent weakness analysis — opening repertoire, common blunders, time pressure patterns
Twin Bot — practice against an AI clone of your opponent's exact playing style
FIDE OTB database — 11 million+ tournament games and 1.7 million+ rated players
Stockfish-powered analysis with depth-25 evaluations
Multi-platform: Lichess, Chess.com, and FIDE in one place
Head-to-head comparison, Nemesis detection, Stalker Score

How it works

Search any Lichess, Chess.com username or FIDE player
Get instant scouting report with weaknesses and patterns
Prepare your strategy and practice against the Twin Bot

GM

Kosakowski, Jakub

POL POL·Born 2002·FIDE #1185080·3,048 Games

Classical25492,774 Games

Rapid2536127 Games

Blitz2525169 Games

Statistics

3048

Total

1643

Wins

615

Draws

784

Losses

54%20%26%

Play Style

What you need to know before facing them

Elite accuracy: 93.8% average

Solid conversion: 85%

Very consistent (91%)

Very precise: only 0.1 blunders/game

Dominates 1.c4 ♔ (81% in 26 games)

Vulnerable to 1.b3 ♚ (only 48%)

Deep Analysis

Stockfish 18 · Classical games · 609 analyzed

Accuracy by phase

Opening96.8%

Middlegame93.6%

Endgame95.3%

Clutch Factor

Performance under pressure

+5%

Winning (+2 or more)95%

234 Games

Equal position95%

177 Games

Losing (-2 or more)90%

89 Games

Problematic Pieces

Which pieces cause most errors?

♖

29%

105 errors

♕

18%

67 errors

♞

16%

57 errors

♙

16%

57 errors

♗

13%

47 errors

♔

9%

33 errors

Critical Moment

When does the first serious error occur?

Move 40average

1-15

16-25

26-35

36-45

46+

42% of blunders occur between move 26-35. Keep tension until that moment.

Error Heatmap

Where do most errors occur?

10

11

10

12

14

10

11

10

12

10

abcdefgh

Many

Few

Critical squares

d514 err

c512 err

f212 err

e611 err

f511 err

d5/c5 concentrate most errors. Force decisions in those zones.

Recent Games

D

Sevian, Samuel2696

Titled Tue 26th May 2026 · 26 May 2026

½-½

W

Rohwer, Paul2020

Titled Tue 26th May 2026 · 26 May 2026

0-1

L

Pranav,V2657

Titled Tue 26th May 2026 · 26 May 2026

0-1

W

Kona, Vidip2082

Titled Tue 26th May 2026 · 26 May 2026

0-1

W

Dang, Duy Linh2128

Titled Tue 26th May 2026 · 26 May 2026

1-0

W

Bluebaum, Matthias2694

Titled Tue 26th May 2026 · 26 May 2026

0-1

Openings

Based on player games

Weaknesses

EXPLOIT!

White

No significant weaknesses detected as White

Black

1.b3 g6 2.Bb2 Nf6

53.3%

15 Games·Loses

1.b3 g6 2.Bb2 Nf6

Strengths

AVOID

White

Slav Defense

75.0%

12 Games·Wins

1.d4 d5 2.c4 c6

Sicilian: e6 Systems

58.5%

130 Games·Wins

1.e4 c5 2.Nf3 e6

Black

Sicilian: d6 Systems

53.2%

203 Games·Wins

1.e4 c5 2.Nf3 d6

Caro-Kann: Main Line

66.7%

24 Games·Wins

1.e4 c6 2.d4 d5 3.Nc3 dxe4

Critical Blunders

Tactical errors analyzed with Stockfish

10 errors

▶

#37Kb1??

Tactics

vs Suleimen

Blitz·2025

▶

#27Kh8??

Tactics

vs Niemann

Blitz·2025

▶

#44Ng6??

Endgame

vs Robson

Blitz·2025

▶

#21a6??

Tactics

vs Fandi

Blitz·2025

▶

#30Nc4??

Tactics

vs Giri

Blitz·2025

▶

#36Qd6??

Tactics

vs Dau Khuong Duy

Blitz·2025

▶

#58Rb3+??

Endgame

vs Nihal Sarin

Blitz·2025

▶

#19Nxf6??

Tactics

vs Motylev

Rapid·2025

▶

#46Rc4+??

Endgame

vs Giri

Rapid·2025

▶

#50g5??

Endgame

vs Sevian

Blitz·2025

Endgame Statistics

23 endgame categories analyzed — discover where they collapse under pressure

Repertoire

☰ All

♟ Classical

⚡ Rapid

🔥 Blitz

PRO

·

2026

2025

2024

2023

2022

2021

PRO

8

7

6

5

4

3

2

1a

b

c

d

e

f

g

h

Starting Position

1538 Games

57%20%23%

Move	Games	Performance	%
1.e4	1267		65%
1.d4 Strong	149		77%
1.Nf3 Strong	66		79%
1.c4 Strong	26		81%
1.b3	4		50%
1.Nc3 Strong	4		100%
1.g3	3		33%
1.a3	3		33%
1.f4 Weak	2		25%
1.d3	2		50%
1.b4 Weak	2		0%
1.g4	2		50%
1.Nh3 Strong	1		100%
1.Na3 Strong	1		100%
1.e3 Strong	1		100%
1.c3 Strong	1		100%
1.h4 Strong	1		100%
1.a4 Strong	1		100%
1.h3 Strong	1		100%
1.f3 Strong	1		100%

1.e4

65%

1267

1.d4

77%

149

1.Nf3

79%

66

1.c4

81%

26

1.b3

50%

4

1.Nc3

100%

4

1.g3

33%

3

1.a3

33%

3

1.f4

25%

2

1.d3

50%

2

1.b4

0%

2

1.g4

50%

2

1.Nh3

100%

1

1.Na3

100%

1

1.e3

100%

1

1.c3

100%

1

1.h4

100%

1

1.a4

100%

1

1.h3

100%

1

1.f3

100%

1

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