KNSB FIDE
BK

Bert Koster

Rated since January 2023

1831 Classic
1831 Rapid
1831 Blitz

RIVALRY

Nemesis
Scholten, E. (Evert)
Games: 6 · Win rate: 50%
Kryptonite
Kamminga, W.R. (Rob)
Games: 8 · Win rate: 0%
Easy Target
Harmanny, W. (Wim)
Games: 4 · Win rate: 100%

The good & the bad

Best wins
WEPEREN VAN, J.J. (JOS) 1902
11827 S.C. Middelstum interne competitie 03-06-2025 t/m 04-09-2025 (020024) · Tuesday 8 July 2025
BOL, J. (JAN) 1850
11828 S.C. Middelstum interne competitie 04-06-2025 t/m 05-09-2025 (020024) · Thursday 24 July 2025
BRANDSMA, F. (FRITS) 1822
11828 S.C. Middelstum interne competitie 04-06-2025 t/m 05-09-2025 (020024) · Friday 5 September 2025
HOF, J.M. (JAN MARK) 1766
11828 S.C. Middelstum interne competitie 04-06-2025 t/m 05-09-2025 (020024) · Wednesday 30 July 2025
SCHOLTEN, E. (EVERT) 1726
11827 S.C. Middelstum interne competitie 03-06-2025 t/m 04-09-2025 (020024) · Tuesday 5 August 2025
Worst losses
PEEK, J.C. (JAN) 1310
7931 NOSBO competitie 2023-2024 November 2023 · Tuesday 31 October 2023
TOXOPÉUS, C. (CARSTEN) 1660
6984 NOSBO competitie 2022-2023 April 2023 · Tuesday 11 April 2023
BRANDSMA, F. (FRITS) 1682
5867 interne competitie SC Middelstum 2022-2023 Groep A · Tuesday 14 March 2023
HOF, J.M. (JAN MARK) 1694
5867 interne competitie SC Middelstum 2022-2023 Groep A · Tuesday 4 October 2022
MOLEWIJK, K. (KOEN) 1709
10558 NOSBO competitie 2024-2025 Februari 2025 · Tuesday 11 February 2025
Chessfestival Groningen Seniorentoernooi - Friday 26 December 2025 +0–1=3 -30.5
NOSBO-competitie 2025-2026 ronde 6 (minus één uitgestelde wedstrijd)… Monday 16 March 2026 +1–0=0
NOSBO-competitie 2025-2026 ronde 5 (minus één uitgestelde wedstrijd)… Monday 16 February 2026 +0–1=0 -13.5
NOSBO-competitie 2025-2026 ronde 4 Groep A Monday 19 January 2026 +0–0=1 -1.5
S.C. Middelstum interne competitie 08-01-2026 t/m 26-02-2026 (020024) Thursday 1 January 2026 +2–2=1 -14.5
NOSBO-competitie 2025-2026 ronde 3 Groep A Friday 28 November 2025 +0–0=1 -4.5
NOSBO-competitie 2025-2026 ronde 2 Groep A Monday 10 November 2025 +0–1=0 -16.3
S.C. Middelstum interne competitie 07-10-2025 t/m 16-12-2025 (020024) Tuesday 9 September 2025 +3–2=3 -22.9
S.C. Middelstum interne competitie 09-09-2025 t/m 30-09-2025 (020024) Tuesday 9 September 2025 +1–0=3 +15.2
S.C. Middelstum interne competitie 04-06-2025 t/m 05-09-2025 (020024) Wednesday 4 June 2025 +8–1=4 +91.7
S.C. Middelstum interne competitie 03-06-2025 t/m 04-09-2025 (020024) Tuesday 3 June 2025 +9–1=2 +86.5
NOSBO competitie 2024-2025 Februari 2025 Wednesday 1 January 2025 +1–1=0 -14.1
NOSBO-competitie 2023-2024 April 2024 Sunday 1 October 2023 +1–0=0 +8.5
NOSBO competitie 2023-2024 November 2023 Sunday 1 October 2023 +0–1=0 -21.1
NOSBO competitie 2022-2023 April 2023 Monday 24 October 2022 +0–1=0 -4.7
interne competitie SC Middelstum 2022-2023 Groep A Tuesday 13 September 2022 +7–5=5 +32.8

Rating History

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Peak Ratings

Classic 1934 Nov. 1, 2025
Rapid 1831 March 1, 2026
Blitz 1831 March 1, 2026

Games

Wins 33
Losses 17
Draws 23
Win Rate 45%

Performance by Color

Color Wins Draws Losses Win Rate
White 17 10 10 46%
Black 16 13 7 44%

Recent Matches

Kleine de, R.F. (Roderick) Tuesday 17 March 2026 WIN
Scholten, E. (Evert) (1723) Thursday 26 February 2026 LOSS -17.1
Welling, S.C. (Sophie) (1830) Friday 20 February 2026 LOSS -13.5
Kamminga, W.R. (Rob) (2014) Thursday 19 February 2026 LOSS -7.3
Prins, B.H. (Be) (1663) Wednesday 4 February 2026 WIN +6.2
Harmanny, W. (Wim) (1587) Thursday 29 January 2026 WIN +3.6
Spears, R. (Russell) (1849) Tuesday 20 January 2026 DRAW -1.5
Weperen van, J.J. (Jos) (1895) Wednesday 14 January 2026 DRAW +0.1
Ridder de, H.P.L. (Henk) (1764) Tuesday 30 December 2025 DRAW -5.1
Karsdorp, G.N. (Nico) (1836) Monday 29 December 2025 DRAW -2.8
Mostertman, J.L.H. (Johan) (1727) Sunday 28 December 2025 DRAW -6.2
Bosveld, H.E.P. (Henk) (1805) Saturday 27 December 2025 LOSS -16.3
Brandsma, F. (Frits) (1873) Tuesday 16 December 2025 DRAW -1.6
Kamminga, W.R. (Rob) (1973) Tuesday 9 December 2025 LOSS -10.6
Krawczyk, J.J. (Jarek) (1799) Tuesday 2 December 2025 DRAW -4.5
Bekker, F. (Free) (1594) Tuesday 25 November 2025 WIN +2.9
Melle van, J.P. (Joost) (1584) Tuesday 18 November 2025 WIN +2.8
Brandsma, F. (Frits) (1863) Tuesday 11 November 2025 DRAW -2.5
Nair, P. (Pranav Prasobh) (1824) Monday 10 November 2025 LOSS -16.3
Scholten, E. (Evert) (1756) Tuesday 28 October 2025 DRAW -5.4