JK

Jan Koolstra

Rated since January 2023

1605 Classic
1483 Rapid
1600 Blitz

RIVALRY

Nemesis
Looman, J.F.M. (Hans)
Games: 6 · Win rate: 50%
Kryptonite
Koolstra, J. (Jacques)
Games: 6 · Win rate: 0%
Easy Target
Kraay, J. (Jos)
Games: 6 · Win rate: 100%

The good & the bad

Best wins
RAN, M. (MART) 1805
14154 S.V. EsPion interne competitie 06-07-2026 t/m 27-07-2026 (080015) · Monday 20 July 2026
VELLEKOOP, A. (ALFRED) 1735
11208 S.V. EsPion interne competitie 31-03-2025 t/m 28-04-2025 (080015) · Monday 31 March 2025
KOK, P. (PIETER) 1702
8654 EsPion interne competitie 2023-2024 Voorjaar ronde 2-5 · Monday 11 March 2024
MERKUL, E. (EUGEN) 1677
13136 S.V. EsPion interne competitie 01-06-2026 t/m 01-06-2026 (080015) · Monday 1 June 2026
MANK, A.H.C. (AD) 1666
8654 EsPion interne competitie 2023-2024 Voorjaar ronde 2-5 · Monday 26 February 2024
Worst losses
HILLEBRAND, J.B.N.M. (JOS) 1348
8119 EsPion interne competitie 2023-2024 Ronde 9 - 11 · Monday 4 December 2023
SCHALEKAMP, R. (ROB) 1442
6271 EsPion Interne competitie 2022-2023 Najaar 2022 ronde 10-13 · Monday 19 December 2022
STOLP, H.P. (PETER) 1444
14213 S.V. EsPion interne competitie 03-08-2026 t/m 24-08-2026 (080015) · Monday 24 August 2026
PLANTFEBER, H.J. (HENK) 1468
6784 EsPion Interne competitie 2022-2023 Voorjaar 2023 ronde 4 - 7 · Monday 27 February 2023
MERKUL, E. (EUGEN) 1476
8309 EsPion interne competitie 2023-2024 Ronde 12 - 14 · Monday 15 January 2024
No FIDE-rated tournaments found.
S.V. EsPion interne competitie 03-08-2026 t/m 24-08-2026 (080015) Monday 8 June 2026 +0–5=0 -38.8
S.V. EsPion interne competitie 06-07-2026 t/m 27-07-2026 (080015) Monday 8 June 2026 +3–6=1 -10.4
S.V. EsPion interne competitie 15-06-2026 t/m 06-08-2026 (080015) Monday 8 June 2026 +0–6=0 -52.6
S.V. EsPion interne competitie 01-06-2026 t/m 01-06-2026 (080015) Monday 2 February 2026 +1–0=0 +15.5
S.V. EsPion interne competitie 11-05-2026 t/m 25-05-2026 (080015) Monday 2 February 2026 +0–1=0 -7.5
S.V. EsPion interne competitie 31-03-2026 t/m 20-04-2026 (080015) Monday 2 February 2026 +1–0=1 +11.8
S.V. EsPion interne competitie 02-03-2026 t/m 23-03-2026 (080015) Monday 2 February 2026 +1–2=0 -6.9
S.V. EsPion interne competitie 02-02-2026 t/m 23-02-2026 (080015) Monday 2 February 2026 +1–2=0 -8.3
SGA Competitie 2025-2026 Viertallen ronde 6 en 7 Wednesday 1 October 2025 +0–1=0 -16.1
S.V. EsPion interne competitie 05-01-2026 t/m 26-01-2026 (080015) Monday 22 September 2025 +1–1=0 -7.9
S.V. EsPion interne competitie 01-12-2025 t/m 22-12-2025 (080015) Monday 22 September 2025 +1–0=1 +6.5
S.V. EsPion interne competitie 03-11-2025 t/m 24-11-2025 (080015) Monday 22 September 2025 +0–1=2 -7.9
S.V. EsPion interne competitie 29-09-2025 t/m 27-10-2025 (080015) Monday 22 September 2025 +1–2=0 +0.1
S.V. EsPion interne competitie 22-09-2025 t/m 22-09-2025 (080015) Monday 22 September 2025 +0–0=1 +6.6
S.V. EsPion interne competitie 28-07-2025 t/m 25-08-2025 (080015) Monday 2 June 2025 +1–6=0 -47.2
S.V. EsPion interne competitie 30-06-2025 t/m 21-07-2025 (080015) Monday 2 June 2025 +3–2=0 +3.7
S.V. EsPion interne competitie 02-06-2025 t/m 23-06-2025 (080015) Monday 2 June 2025 +4–1=1 +11.2
S.V. EsPion interne competitie 12-05-2025 t/m 26-05-2025 (080015) Monday 3 February 2025 +1–1=1 +4.2
S.V. EsPion interne competitie 31-03-2025 t/m 28-04-2025 (080015) Monday 3 February 2025 +1–2=0 +5.8
S.V. EsPion interne competitie 03-03-2025 t/m 24-03-2025 (080015) Monday 3 February 2025 +1–1=0 -1.0
S.V. EsPion interne competitie 03-02-2025 t/m 24-02-2025 (080015) Monday 3 February 2025 +1–2=1 +2.0
S.V. EsPion interne competitie 27-01-2025 t/m 27-01-2025 (080015) Monday 23 September 2024 +1–0=0 +9.6
S.V. EsPion interne competitie 06-01-2025 t/m 20-01-2025 (080015) Monday 23 September 2024 +1–1=0 -2.7
S.V. EsPion interne competitie 28-10-2024 t/m 23-12-2024 (080015) Monday 23 September 2024 +2–4=3 -23.2
S.V. EsPion interne competitie 23-09-2024 t/m 21-10-2024 (080015) Monday 23 September 2024 +0–2=1 -11.4
EsPion interne competitie 2023-2024 Voorjaar ronde 15-17 Monday 2 October 2023 +1–0=1 +9.7
EsPion interne competitie 2023-2024 Voorjaar ronde 11-14 Monday 2 October 2023 +1–1=1 -10.6
EsPion interne competitie 2023-2024 Voorjaar ronde 6-10 Monday 2 October 2023 +0–2=1 -15.8
EsPion interne competitie 2023-2024 Voorjaar ronde 2-5 Monday 2 October 2023 +2–2=0 +21.9
EsPion interne competitie 2023-2024 Ronde 15 - 17 Monday 2 October 2023 +1–1=0 -8.1
EsPion interne competitie 2023-2024 Ronde 12 - 14 Monday 2 October 2023 +1–2=0 -17.6
EsPion interne competitie 2023-2024 Ronde 9 - 11 Monday 2 October 2023 +1–1=1 -16.2
EsPion interne competitie 2023-2024 Ronde 5-8 Monday 2 October 2023 +1–1=0 +4.6
EsPion interne competitie 2023-2024 Ronde 1-4 Monday 2 October 2023 +1–1=0 +0.2
SGA Competitie 2022-2023 3e Klasse B ronde 3 Saturday 1 October 2022 +0–1=0
EsPion Interne competitie 2022-2023 Voorjaar 2023 ronde 17 Monday 26 September 2022 +0–0=1 +4.8
EsPion Interne competitie 2022-2023 Voorjaar 2023 ronde 13 - 16 Monday 26 September 2022 +2–2=0 +13.2
EsPion Interne competitie 2022-2023 Voorjaar 2023 ronde 8 - 12 Monday 26 September 2022 +0–1=2 +4.7
EsPion Interne competitie 2022-2023 Voorjaar 2023 ronde 4 - 7 Monday 26 September 2022 +2–1=1 +10.2
EsPion Interne competitie 2022-2023 Voorjaar 2023 ronde 1 - 3 Monday 26 September 2022 +1–1=0 +18.1
EsPion Interne competitie 2022-2023 Najaar 2022 Ronde 14-16 Monday 26 September 2022 +2–1=0 +8.4
EsPion Interne competitie 2022-2023 Najaar 2022 ronde 10-13 Monday 26 September 2022 +2–2=0 -10.1

Team Competition

Current team
EsPion 4
Viertallen · 2025-2026 · 2 games

Rating History

Loading rating history...

Peak Ratings

Classic 1650 April 1, 2024
Rapid 1632 Aug. 1, 2025
Blitz 1607 March 1, 2026

Games

Wins 44
Losses 69
Draws 21
Win Rate 33%

Performance by Color

Color Wins Draws Losses Win Rate
White 20 10 36 30%
Black 24 11 33 35%

Recent Matches

Stolp, H.P. (Peter) (1444) Monday 24 August 2026 LOSS -15.2
Jong, C. (Casijn) (1962) Monday 24 August 2026 LOSS -1.5
Dekker, C. (Constantijn) (1997) Monday 24 August 2026 LOSS -1.2
Bezemer, C. (Casper) (1481) Monday 17 August 2026 LOSS -13.9
Stokman, L.N. (Lennart) (1691) Monday 17 August 2026 LOSS -6.9
Kerkhoff, F.C. (Frans) (1580) Monday 27 July 2026 LOSS -12.7
Koolstra, J. (Jacques) (1625) Monday 27 July 2026 LOSS -11.1
Boom, H. (Harrie) (1563) Monday 20 July 2026 WIN +11.7
Ran, M. (Mart) (1805) Monday 20 July 2026 WIN +19.5
Steensma, F. (Frank) (1715) Monday 20 July 2026 LOSS -8.1
Heima, H.J.M. (Henny) (1597) Monday 13 July 2026 LOSS -12.1
Admiraal, R.M. (Ron) (1646) Monday 13 July 2026 LOSS -10.4
Slooten van, R. (Rob) (1727) Monday 6 July 2026 DRAW +4.8
Vaassen, M. (Mick) (1512) Monday 6 July 2026 WIN +10.0
Eijk van der, D. (Dick) (1990) Monday 6 July 2026 LOSS -2.0
Pelleboer, P. (Pieter) (1853) Monday 29 June 2026 LOSS -4.4
Kips, D. (David) (1651) Monday 29 June 2026 LOSS -10.2
Dernier, R.P. (Raymond) (1752) Monday 29 June 2026 LOSS -7.0
Rijn van, A. (André) (1667) Monday 15 June 2026 LOSS -9.7
Schalekamp, R. (Rob) (1659) Monday 15 June 2026 LOSS -10.0