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

IM

Peyrer, Konstantin

AUT AUT·Born 2003·FIDE #1640879·1,230 Games

Classical2496941 Games

Rapid2480155 Games

Blitz2528202 Games

Statistics

1230

Total

548

Wins

351

Draws

327

Losses

45%29%27%

Play Style

What you need to know before facing them

Elite accuracy: 93.1% average

Solid conversion: 81%

Very consistent (91%)

Very precise: only 0.1 blunders/game

Dominates 1.e4 ♔ (66% in 150 games)

Vulnerable to 1.c4 ♚ (only 39%)

Deep Analysis

Stockfish 18 · Classical games · 418 analyzed

Accuracy by phase

Opening96.1%

Middlegame92.8%

Endgame94.7%

Clutch Factor

Performance under pressure

+5%

Winning (+2 or more)94%

162 Games

Equal position94%

171 Games

Losing (-2 or more)89%

85 Games

Problematic Pieces

Which pieces cause most errors?

♖

26%

90 errors

♙

20%

69 errors

♗

15%

52 errors

♞

14%

51 errors

♕

14%

51 errors

♔

11%

39 errors

Critical Moment

When does the first serious error occur?

Move 41average

1-15

16-25

26-35

36-45

46+

32% of blunders occur between move 46+. Keep tension until that moment.

Error Heatmap

Where do most errors occur?

11

10

13

11

14

14

11

8

9

9

abcdefgh

Many

Few

Critical squares

f514 err

g514 err

d513 err

d811 err

e511 err

f5/g5 concentrate most errors. Force decisions in those zones.

Recent Games

W

Mohr, Georg2389

Grand Prix PlusCity Blitz · 15 May 2026

0-1

L

Postlmayer, Jakob2438

Grand Prix PlusCity Blitz · 15 May 2026

0-1

L

Malek,Jan2560

Grand Prix PlusCity Blitz · 15 May 2026

0-1

L

Santos Latasa, Jaime2615

Grand Prix PlusCity Blitz · 15 May 2026

1-0

L

Glek, Igor2423

Grand Prix PlusCity Blitz · 15 May 2026

0-1

D

Risteski, Emil2408

Grand Prix PlusCity Blitz · 15 May 2026

½-½

Openings

Based on player games

Weaknesses

EXPLOIT!

White

Nimzo-Indian: Rubinstein

44.4%

27 Games·Loses

1.d4 Nf6 2.c4 e6 3.Nc3 Bb4 4.e3

Black

Italian: Two Knights

52.6%

19 Games·Loses

1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6

Strengths

AVOID

White

Sicilian: e6 Systems

60.0%

20 Games·Wins

1.e4 c5 2.Nf3 e6

Reti: Double Fianchetto

60.0%

10 Games·Wins

1.Nf3 Nf6 2.g3 d5

Black

Ruy Lopez: Morphy

53.7%

54 Games·Wins

1.e4 e5 2.Nf3 Nc6 3.Bb5 a6

Reti vs King's Indian

55.6%

18 Games·Wins

1.Nf3 Nf6 2.c4 g6

Critical Blunders

Tactical errors analyzed with Stockfish

10 errors

▶

#39Nc6??

Tactics

vs Harshavardhan G B

Blitz·2025

▶

#56Rxf7??

Endgame

vs Gaehwiler

Blitz·2025

▶

#41Nf6+??

Endgame

vs Grebnev

Blitz·2025

▶

#22Qf4??

Tactics

vs Galaviz Medina

Blitz·2025

▶

#20Bf4??

Tactics

vs Sindarov

Blitz·2025

▶

#17Rf7??

Tactics

vs Yu

Blitz·2025

▶

#47Re4??

Endgame

vs Ahmad

Blitz·2025

▶

#32Nd2??

Tactics

vs Kozak

Rapid·2025

▶

#39Rc1??

Endgame

vs Giri

Blitz·2025

▶

#23Bb2??

Tactics

vs Musovic

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

600 Games

48%30%22%

Move	Games	Performance	%
1.d4	210		62%
1.e4	153		65%
1.Nf3	151		66%
1.c4	68		57%
1.g3	7		43%
1.e3	5		40%
1.a3 Strong	2		100%
1.f4	2		50%
1.b3	2		50%

1.d4

62%

210

1.e4

65%

153

1.Nf3

66%

151

1.c4

57%

68

1.g3

43%

7

1.e3

40%

5

1.a3

100%

2

1.f4

50%

2

1.b3

50%

2

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