KNSB FIDE
KS

Klaas Siewertsen

Rated since January 2023

1515 Classic
1503 Rapid
1503 Blitz

Team Competition

Current teams
WSC
Bronzen Beker · 2025-2026 · 1 game
WSC 1
Viertallen · 2025-2026 · 6 games
Past teams
WSC 1
Viertallen · 2024-2025
5 games
WSC 1
Viertallen · 2023-2024
8 games

RIVALRY

Not enough games to determine rivalries yet.

The good & the bad

Best wins
KOOLSTRA, J.R. (JAN) 1607
13647 SGA Competitie 2025-2026 Viertallen ronde 6 en 7 · Monday 30 March 2026
BAJNATH, A. (AMRESH) 1343
11616 UniClass Science Park Amsterdam Schaaktoernooi Groep C · Sunday 13 July 2025
JANSWEIJER, M. (MAARTEN) 1200
11616 UniClass Science Park Amsterdam Schaaktoernooi Groep C · Friday 11 July 2025
Worst losses
BOORDER DE, M. (MARK) 1425
11357 SGA Competitie 2024-2025 Viertallen ronde 8 en 9 · Monday 12 May 2025
GULAVE, D. (DEVRAN) 1460
11647 De Volewijckers Weekendvierkamp 2025 Groep 11 · Saturday 5 July 2025
LOVISOTTO, K. (KEVIN) 1490
12486 SGA Competitie 2025-2026 Bronzen Beker ronde 1 · Tuesday 11 November 2025
LAGRAND, T.H.M. (DICK) 1573
11647 De Volewijckers Weekendvierkamp 2025 Groep 11 · Saturday 5 July 2025
ERSÖZ, B.H. (BARIS) 1631
13837 SGA Competitie 2025-2026 Viertallen ronde 7 · Tuesday 19 May 2026
UniClass Science Park Amsterdam Schaaktoernooi Groep C Saturday 5 July 2025 +2–3=3 -7.1
SGA Competitie 2025-2026 Viertallen ronde 7 Wednesday 1 October 2025 +0–1=0 -4.3
SGA Competitie 2025-2026 Viertallen ronde 6 en 7 Wednesday 1 October 2025 +2–0=0 +32.1
SGA Competitie 2025-2026 Viertallen ronde 4 en 5 Wednesday 1 October 2025 +0–1=1 -7.6
SGA Competitie 2025-2026 Viertallen ronde 3 Wednesday 1 October 2025 +0–0=1 +4.0
SGA Competitie 2025-2026 Bronzen Beker ronde 1 Wednesday 1 October 2025 +0–1=0 -13.6
SGA Competitie 2025-2026 Viertallen ronde 1 en 2 Wednesday 1 October 2025 +0–0=1 +7.4
De Volewijckers Weekendvierkamp 2025 Groep 11 Friday 4 July 2025 +0–3=0 -27.2
SGA Competitie 2024-2025 Viertallen ronde 8 en 9 Monday 30 September 2024 +0–1=0 -17.2

Rating History

Loading rating history...

Peak Ratings

Classic 1638 April 1, 2024
Rapid 1503 March 1, 2026
Blitz 1503 March 1, 2026

Games

Wins 4
Losses 10
Draws 6
Win Rate 20%

Performance by Color

Color Wins Draws Losses Win Rate
White 2 2 5 22%
Black 2 4 5 18%

Recent Matches

Ersöz, B.H. (Baris) (1631) Tuesday 19 May 2026 LOSS -4.3
Koolstra, J.R. (Jan) (1607) Monday 30 March 2026 WIN +16.1
Koolstra, J.R. (Jan) (1607) Monday 30 March 2026 WIN +16.1
Eusman, R.M. (Ruben) (1658) Tuesday 24 February 2026 LOSS -7.6
Spiekerman, E. (Emile) Thursday 5 February 2026 DRAW
Beekhuis, L. (Lennart) (1624) Tuesday 2 December 2025 DRAW +4.0
Lovisotto, K. (Kevin) (1490) Tuesday 11 November 2025 LOSS -13.6
Lijklema, Y. (Ynte) (1752) Tuesday 7 October 2025 DRAW +7.4
Bajnath, A. (Amresh) (1343) Sunday 13 July 2025 WIN +5.9
Sommer, H. (Hugo) (1676) Saturday 12 July 2025 LOSS -8.2
Jansweijer, M. (Maarten) (1200) Friday 11 July 2025 WIN +2.8
Leijdekkers, T. (Tom) (1451) Thursday 10 July 2025 DRAW -3.3
Haaften van, R. (Rob) (1606) Wednesday 9 July 2025 DRAW +2.0
Poel, J.E. (Jacob) (1540) Tuesday 8 July 2025 DRAW -0.3
Groot de, J. (Joris) (1748) Monday 7 July 2025 LOSS -6.1
Roels, S.T. (Tobias) Sunday 6 July 2025 LOSS
Gulave, D. (Devran) (1460) Saturday 5 July 2025 LOSS -15.5
Lagrand, T.H.M. (Dick) (1573) Saturday 5 July 2025 LOSS -11.6
Sterren van der, T. (Teun) Friday 4 July 2025 LOSS
Boorder de, M. (Mark) (1425) Monday 12 May 2025 LOSS -17.2