Chess South Africa Ratings Database

PLAYER PAGE

Personal

Koster, W (Wihan)

Chess SA id

1060134033

FIDE id

Date of birth

2006-12-13 (U20)

Gender

Male

Region

Tshwane (GTP)

Citizen

RSA

Titles

Chess SA registered

Last active game

2025-08-16

Personal details last changed

1900-01-01

Junior GPX Games

12.9

Junior GPX Points

1373.4

Item	Main	Standard	Rapid	Blitz
Rating	1443.4	1447.9	1230.1	1200
Raw rating	1443.4	1447.9	1230.1	1200
Weighted rating	1417.4	1418.5	1227.3	1200
Weighted performance	1316.6	1367.9	0	0
Floor	947.6	947.9	748.2	700
K-factor	32	32	36	36
Min/Max rating change allowed	117.2	116.5	158.9	165.8
Highest rating	1647.6 2021-04-01	1644.1 2021-04-01	1388.5 2021-10-01	1200 2018-10-01
Highest raw rating	1447.6 2023-07-01	1447.9 2025-09-01	1248.2 2024-02-01	1200 2024-02-01
Highest weighted rating	1447.6 2024-08-01	1440.4 2024-08-01	1248.2 2024-09-01	1200 2018-10-01
Highest weighted performance	1647.6 2021-04-01	1644.1 2021-04-01	1388.5 2021-10-01	1200 2024-02-01

Prediction
Item	Main	Standard	Rapid	Blitz
Rating change	0	0	0	0
New rating	1443.4	1447.9	1230.1	1200
Analysis
Rating	1443.4	1447.9	1230.1	1200
Raw rating	1443.4	1447.9	1230.1	1200
Weighted rating	1417.4	1418.5	1227.3
Weighted performance	1316.6	1367.9	0
K-factor	32	32	36	36
Floor	947.6	947.9	748.2	700
Max/Min rating change allowed	117.2	116.5	158.9	165.8
Games	0	0	0	0
Score	0	0	0	0
Expected score	0	0	0	0
Score-Expected	0	0	0	0
Temp raw +/-	0	0	0	0
Final raw +/-	0	0	0	0
New raw rating	1443.4	1447.9	1230.1	1200
New weighted rating	1419.5	1421.2	1227.1	1200
New weighted performance	1316.1	1367.4	0	0
Temp new rating	1443.4	1447.9	1230.1	1200
Temp new rating +/-	0	0	0	0
Final new rating +/-	0	0	0	0
New rating	1443.4	1447.9	1230.1	1200
New K-factor	32	32	36	36
New floor	947.6	947.9	748.2	700

Item	Main	Standard	Rapid
	0	0	0
	5	5	0
	35	30	5
	29	29	0
	50	43	7
	27	22	5
History	146	129	17

Games since
	Main 40	Standard 35		Rapid 5		Blitz 0
Gender	Male
Age group	U20
Region	Tshwane (GTP)
Province	Gauteng (GT)
Main
	RSA		Province		Region
Overall	1728		598		219
Male	1454		490		175
U20	155		49		17
U20 Male	130		38		13
Standard
	RSA		Province		Region
Overall	1591		585		220
Male	1330		479		177
U20	143		50		19
U20 Male	115		38		15
Rapid
	RSA		Province		Region
Overall	-1		-1		-1
Male	-1		-1		-1
U20	-1		-1		-1
U20 Male	-1		-1		-1
Blitz
	RSA		Province		Region
Overall	-1		-1		-1
Male	-1		-1		-1
U20	-1		-1		-1
U20 Male	-1		-1		-1


	Games	Score	%	Dp	AvgOpp	Performance
Main	0	0	0	0	0	0
Standard	0	0	0	0	0	0
Rapid	0	0	0	0	0	0
Blitz	0	0	0	0	0	0

	Games	Score	%	Dp	AvgOpp	Performance
Main	5	4.5	90	340	1270.6	1610.6
Standard	5	4.5	90	340	1270.6	1610.6
Rapid	0	0	0	0	0	0
Blitz	0	0	0	0	0	0
History
	Games	Score	%	Dp	AvgOpp	Performance
Main	146	88	60.27	87.3	1337	1424.4
Standard	129	77.5	60.08	85.7	1342.8	1428.4
Rapid	17	10.5	61.76	100	1293.6	1393.6
Blitz	0	0	0	0	0	0

Date	Main	Standard	Rapid	Blitz
2025-09-30	1443.4	1447.9	1230.1	1200
2025-09-01	1443.4	1447.9	1230.1	1200
2025-08-01	1413.5	1412.7	1230.1	1200
2025-07-01	1413.5	1412.4	1230.1	1200
2025-06-01	1413.5	1412.3	1230.1	1200
2025-05-01	1413.5	1412.2	1230.1	1200
2025-04-01	1413.5	1412.2	1230.1	1200
2025-03-01	1413.5	1412.2	1230.1	1200
2025-02-01	1412.2	1412.1	1227	1200
2025-01-01	1389.5	1410.7	1177.6	1200
2024-12-01	1386.8	1408.8	1177.6	1200
2024-11-01	1386.8	1408.8	1177.6	1200
2024-10-01	1417.4	1408.8	1248.2	1200
2024-09-01	1417.4	1408.8	1248.2	1200
2024-08-01	1431.7	1426.4	1248.2	1200
2024-07-01	1431.7	1426.4	1248.2	1200
2024-06-01	1431.7	1426.4	1248.2	1200
2024-08-01	1426.9	1418.4	1248.2	1200
2024-04-01	1426.9	1418.4	1248.2	1200
2024-03-01	1421.2	1409.8	1248.2	1200
2024-02-01	1439.3	1429.6	1248.2	1200
2024-01-01	1405.9	1391.8	1248.2	1200
2023-12-01	1405.9	1391.8	1248.2	1200
2023-11-01	1405.9	1391.8	1248.2	1200

Comming soon.

Tournaments

History

No tournaments found.

#	Tournament	Start	End	Type	Host	Rounds	Games	Score	Cfr	Analysis

#	Tournament	Start	End	Type	Host	Rounds	Games	Score	Cfr	Analysis
1	2025 Tshwane South School District CLOSED League Championship (U19A)	2025-08-16	2025-08-16	Standard	Tshwane (GTP)	5	5	4.5	Yes	Analysis

Last 500 tournaments since 01 January 2018

#	Tournament	Start	End	Type	Host	Rounds	Games	Score	Cfr	Analysis
1	2025 Tshwane South School District CLOSED League Championship (U19A)	2025-08-16	2025-08-16	Standard	Tshwane (GTP)	5	5	4.5	Yes	Analysis
2	Gauteng Inter-Region at UJ 2024 (U20)	2024-12-07	2024-12-08	Standard	Johannesburg Metro (GJM)	5	5	1	Yes	Analysis
3	Gauteng Top Schools 2024 (U19 Open)	2024-10-05	2024-10-05	Rapid	Ekurhuleni (GE)	5	5	1	Yes	Analysis
4	D4 Tshwane South District Schools Teams Chess Tournament 2024 (U19A)	2024-08-03	2024-08-03	Standard	Tshwane (GTP)	5	5	2.5	Yes	Analysis
5	2024 Tshwane South School District CLOSED Individual Championships (U18 Mixed)	2024-05-11	2024-05-11	Standard	Tshwane (GTP)	5	5	3.5	Yes	Analysis
6	2024 Lubowski Open Chess Tournament (C)	2024-03-23	2024-03-24	Standard	Tshwane (GTP)	5	5	3	Yes	Analysis
7	2024 Tshwane Chess AHS Open Chess Tournament (B)	2024-02-24	2024-02-24	Standard	Tshwane (GTP)	5	5	1	Yes	Analysis
8	2024 Gauteng Inter-Region Chess Championship (U18A)	2024-01-13	2024-01-14	Standard	Tshwane (GTP)	5	5	4	Yes	Analysis
9	2023 Gauteng Top Schools (U19 Mixed)	2023-08-19	2023-08-19	Standard	West Rand (GWR)	5	5	2.5	Yes	Analysis
10	2023 Tshwane South School District CLOSED League Championship (U19)	2023-07-29	2023-07-29	Standard	Tshwane (GTP)	5	5	2.5	Yes	Analysis
11	2023 Lubowski Open Tournament (B)	2023-06-24	2023-06-25	Standard	Tshwane (GTP)	5	5	3.5	Yes	Analysis
12	2023 Tshwane South School District CLOSED Individual Championships (U18 Open)	2023-04-22	2023-04-22	Standard	Tshwane (GTP)	5	5	3	Yes	Analysis
13	2023 Afrikaans Ho�r Seunskool Open Chess Tournament (B)	2023-03-04	2023-03-04	Standard	Tshwane (GTP)	5	4	2.5	Yes	Analysis
14	Grey College Team Championship 2023 (A)	2023-02-03	2023-02-04	Standard	Mangaung (FMB)	5	5	4	Yes	Analysis
15	2022 South African Junior Team Chess Championships (U18 Open)	2022-12-04	2022-12-08	Standard	4 Knights (4K)	7	7	3.5	Yes	Analysis
16	Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022	2022-09-22	2022-09-22	Rapid	Tshwane (GTP)	7	7	5.5	Yes	Analysis
17	2022 Etienne Lewis (U18+U20 Open+Girls)	2022-09-02	2022-09-04	Standard	Tshwane (GTP)	7	6	3.5	Yes	Analysis
18	2022 Gauteng Schools Team Championships (U17 Open)	2022-08-26	2022-08-26	Standard	Tshwane (GTP)	5	5	2.5	Yes	Analysis
19	2022 Blou Bul Open (B)	2022-06-25	2022-06-26	Standard	Tshwane (GTP)	5	5	2.5	Yes	Analysis
20	2022 Milos Ristic Open Chess Tournament (C)	2022-05-28	2022-05-28	Standard	Tshwane (GTP)	5	5	4.5	Yes	Analysis
21	2022 Gauteng Interregion (U16 Open)	2022-02-26	2022-02-26	Standard	Tshwane (GTP)	5	5	3	Yes	Analysis
22	Piet Robertse 2022 (C)	2022-02-05	2022-02-05	Standard	Tshwane (GTP)	5	5	2.5	Yes	Analysis
23	Grey College Team Championship 2022 (A)	2022-02-18	2022-02-19	Standard	Mangaung (FMB)	5	5	3	Yes	Analysis
24	2021 Milos Ristic Open (C)	2021-10-09	2021-10-09	Standard	Tshwane (GTP)	5	5	3.5	Yes	Analysis
25	2021 Affies Interhuis	2021-10-28	2021-10-28	Rapid	Tshwane (GTP)	5	5	4	Yes	Analysis
26	2021 Etienne Lewis Closed Trials (U16 Open)	2021-09-24	2021-09-26	Standard	Nelson Mandela Bay (ENM)	7	7	3	Yes	Analysis
27	2021 Lubowski Open Tournament (C)	2021-05-01	2021-05-02	Standard	Tshwane (GTP)	5	5	3.5	Yes	Analysis
28	2021 Blou Bul Tournament (D)	2021-04-10	2021-04-10	Standard	Mangaung (FMB)	5	5	5	Yes	Analysis

#	Games	Start				End
1	7	Tournament 2022 Gauteng Interregion				Tournament 2022 Blou Bul Open
		date 2022-02-26	rnd 5	type Standard	result 1	date 2022-06-25	rnd 1	type Standard	result 0.5
		Opponent Mabaso, J (Jabulani)				Opponent De Beer, J (Janka)
2	6	Tournament 2022 Etienne Lewis				Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022
		date 2022-09-04	rnd 6	type Standard	result 1	date 2022-09-22	rnd 4	type Rapid	result 1
		Opponent Venter, Z (Zanri)				Opponent Kunz, D (Dirk)
3	6	Tournament 2021 Affies Interhuis				Tournament Piet Robertse 2022
		date 2021-10-28	rnd 3	type Rapid	result 1	date 2022-02-05	rnd 3	type Standard	result 0.5
		Opponent Schabort, D (Danie)				Opponent Rammala, TR (Tlale Ronald)

#	Games	Start				End
1	7	Tournament 2022 Gauteng Interregion				Tournament 2022 Blou Bul Open
		date 2022-02-26	rnd 5	type Standard	result 1	date 2022-06-25	rnd 1	type Standard	result 0.5
		Opponent Mabaso, J (Jabulani)				Opponent De Beer, J (Janka)
2	6	Tournament 2021 Blou Bul Tournament				Tournament 2021 Lubowski Open Tournament
		date 2021-04-10	rnd 1	type Standard	result 1	date 2021-05-01	rnd 1	type Standard	result 1
		Opponent Kunz, D (Dirk)				Opponent Louw, N (Nova)
3	5	Tournament 2025 Tshwane South School District CLOSED League Championship				Tournament 2025 Tshwane South School District CLOSED League Championship
		date 2025-08-16	rnd 1	type Standard	result 1	date 2025-08-16	rnd 5	type Standard	result 1
		Opponent Mokake, K (Kwezi)				Opponent Bhudai, A (Arman)

#	Games	Start				End
1	7	Tournament 2021 Affies Interhuis				Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022
		date 2021-10-28	rnd 3	type Rapid	result 1	date 2022-09-22	rnd 4	type Rapid	result 1
		Opponent Schabort, D (Danie)				Opponent Kunz, D (Dirk)
2	2	Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022				Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022
		date 2022-09-22	rnd 6	type Rapid	result 1	date 2022-09-22	rnd 7	type Rapid	result 0.5
		Opponent Fuhri, R (Ruben)				Opponent Mcphail, R (Ryan)
3	1	Tournament Gauteng Top Schools 2024				Tournament Gauteng Top Schools 2024
		date 2024-10-05	rnd 2	type Rapid	result 1	date 2024-10-05	rnd 2	type Rapid	result 1
		Opponent Motloung, M (Mpho)				Opponent Motloung, M (Mpho)

No games found.

#	Games	Start				End

#	Games	Start				End
1	6	Tournament 2021 Blou Bul Tournament				Tournament 2021 Lubowski Open Tournament
		date 2021-04-10	rnd 1	type Standard	result 1	date 2021-05-01	rnd 1	type Standard	result 1
		Opponent Kunz, D (Dirk)				Opponent Louw, N (Nova)
2	5	Tournament 2022 South African Junior Team Chess Championships				Tournament Grey College Team Championship 2023
		date 2022-12-07	rnd 6	type Standard	result 1	date 2023-02-03	rnd 3	type Standard	result 1
		Opponent Kgomo, M (Mathema)				Opponent Beelders, R (Ryan)
3	5	Tournament 2021 Affies Interhuis				Tournament Piet Robertse 2022
		date 2021-10-28	rnd 3	type Rapid	result 1	date 2022-02-05	rnd 2	type Standard	result 1
		Opponent Schabort, D (Danie)				Opponent Mcphail, M (Matthew)

#	Games	Start				End
1	6	Tournament 2021 Blou Bul Tournament				Tournament 2021 Lubowski Open Tournament
		date 2021-04-10	rnd 1	type Standard	result 1	date 2021-05-01	rnd 1	type Standard	result 1
		Opponent Kunz, D (Dirk)				Opponent Louw, N (Nova)
2	5	Tournament 2022 South African Junior Team Chess Championships				Tournament Grey College Team Championship 2023
		date 2022-12-07	rnd 6	type Standard	result 1	date 2023-02-03	rnd 3	type Standard	result 1
		Opponent Kgomo, M (Mathema)				Opponent Beelders, R (Ryan)
3	4	Tournament 2022 Gauteng Interregion				Tournament 2022 Milos Ristic Open Chess Tournament
		date 2022-02-26	rnd 5	type Standard	result 1	date 2022-05-28	rnd 3	type Standard	result 1
		Opponent Mabaso, J (Jabulani)				Opponent Smit, M (Mikayla)

#	Games	Start				End
1	7	Tournament 2021 Affies Interhuis				Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022
		date 2021-10-28	rnd 3	type Rapid	result 1	date 2022-09-22	rnd 4	type Rapid	result 1
		Opponent Schabort, D (Danie)				Opponent Kunz, D (Dirk)
2	1	Tournament Gauteng Top Schools 2024				Tournament Gauteng Top Schools 2024
		date 2024-10-05	rnd 2	type Rapid	result 1	date 2024-10-05	rnd 2	type Rapid	result 1
		Opponent Motloung, M (Mpho)				Opponent Motloung, M (Mpho)
3	1	Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022				Tournament Afrikaanse Ho�r Seunskool Interne Skaak KampioenskAP 2022
		date 2022-09-22	rnd 6	type Rapid	result 1	date 2022-09-22	rnd 6	type Rapid	result 1
		Opponent Fuhri, R (Ruben)				Opponent Fuhri, R (Ruben)

No games found.

#	Games	Start				End

Top 10 opponents most often played

#	Opponent	Main			Standard			Rapid			Blitz
		Gms	Score	Dp	Gms	Score	Dp	Gms	Score	Dp	Gms	Score	Dp
		Gms	Aor	Prat	Gms	Aor	Prat	Gms	Aor	Prat	Gms	Aor	Prat
1	Rautenbach ,H (Helen Christine)	3	0	-425	2	0	-425	1	0	-425	0	0	0
1	Rautenbach ,H (Helen Christine)	3	1634.7	1209.7	2	1620.7	1209.7	1	1073.6	1209.7	0	0	0
2	Gondwe ,P (Prosper)	2	1.5	212.5	2	1.5	212.5	0	0	0	0	0	0
2	Gondwe ,P (Prosper)	2	1371.1	1583.6	2	1369.8	1583.6	0	0	0	0	0	0
3	Slabbert ,ZN (Zander Nicolaas)	2	0	-425	2	0	-425	0	0	0	0	0	0
3	Slabbert ,ZN (Zander Nicolaas)	2	1467.9	1042.9	2	1476.8	1042.9	0	0	0	0	0	0
4	Kruger ,N (Neeke)	2	1	0	2	1	0	0	0	0	0	0	0
4	Kruger ,N (Neeke)	2	1208	1208	2	1203.8	1208	0	0	0	0	0	0
5	Soobramaniyen ,M (Moreshan)	2	1	0	2	1	0	0	0	0	0	0	0
5	Soobramaniyen ,M (Moreshan)	2	1275.7	1275.7	2	1284.2	1275.7	0	0	0	0	0	0
6	Makhafola ,R (Rearabiloe)	2	1	0	2	1	0	0	0	0	0	0	0
6	Makhafola ,R (Rearabiloe)	2	1218.9	1218.9	2	1223	1218.9	0	0	0	0	0	0
7	Oosthuizen ,MJ (Michal Jacobus)	2	0	-425	2	0	-425	0	0	0	0	0	0
7	Oosthuizen ,MJ (Michal Jacobus)	2	1935.2	1510.2	2	1942.4	1510.2	0	0	0	0	0	0
8	Smit ,M (Mikayla)	2	1.5	212.5	2	1.5	212.5	0	0	0	0	0	0
8	Smit ,M (Mikayla)	2	1377.6	1590.1	2	1366.5	1590.1	0	0	0	0	0	0
9	Bhudai ,A (Arman)	2	2	425	2	2	425	0	0	0	0	0	0
9	Bhudai ,A (Arman)	2	1262.4	1687.4	2	1262.7	1687.4	0	0	0	0	0	0
10	Pillay ,K (Ketana)	2	2	425	2	2	425	0	0	0	0	0	0
10	Pillay ,K (Ketana)	2	1330.9	1755.9	2	1314	1755.9	0	0	0	0	0	0

Norms

No norms achieved.

#	Norm	Tournament	Start	End	Rounds	Games	Score	Details

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PLAYER PAGE

Personal

Koster, W (Wihan)

Ratings

Game statistics

Rankings

Historical performance

Last 24 raw ratings

Rating graph

Tournaments

Top 3 Streaks

Top 10 opponents most often played

Norms