PLAYER PAGE
William Jonker
1170192575West Coast (WCU)Personal
Main rating
| Rating | 1200.4 |
| K-factor | 36 |
| Floor | 734.2 |
| Highest | 1275.4 (2024-03-01) |
| Min/Max +/- allowed | 149 |
| Rating Change () | |
| Games | 5 |
| Score | 4 |
| We | 2.44 |
| SWe | 0.94 |
| Temp +/- | 34 |
| Penalties | 0 |
| Weight perform | 1205 |
| Final +/- | 34 |
| New Rating () | |
| Rating | 1234.4 |
| K-factor | 36 |
| Floor | 734.2 |
| Highest | 1275.4 (2024-03-01) |
| Min/Max +/- allowed | 148.9 |
Standard rating
| Rating | 1161.3 |
| K-factor | 36 |
| Floor | 700 |
| Highest | 1200 (2024-02-01) |
| Min/Max +/- allowed | 165.8 |
| Rating Change () | |
| Games | 0 |
| Score | 0 |
| We | 0 |
| SWe | 0 |
| Temp +/- | 0 |
| Penalties | 0 |
| Weight perform | 0 |
| Final +/- | 0 |
| New Rating () | |
| Rating | 1161.3 |
| K-factor | 36 |
| Floor | 700 |
| Highest | 1200 (2024-02-01) |
| Min/Max +/- allowed | 165.8 |
Rapid rating
| Rating | 1246.6 |
| K-factor | 36 |
| Floor | 755.1 |
| Highest | 1343.5 (2024-03-01) |
| Min/Max +/- allowed | 135.2 |
| Rating Change () | |
| Games | 5 |
| Score | 4 |
| We | 2.64 |
| SWe | 1.36 |
| Temp +/- | 49.1 |
| Penalties | 0 |
| Weight perform | 1268 |
| Final +/- | 49.1 |
| New Rating () | |
| Rating | 1295.7 |
| K-factor | 36 |
| Floor | 755.1 |
| Highest | 1343.5 (2024-03-01) |
| Min/Max +/- allowed | 135.2 |
Blitz rating
| Rating | 1200 |
| K-factor | 36 |
| Floor | 700 |
| Highest | 1200 (2024-02-01) |
| Min/Max +/- allowed | 165.8 |
| Rating Change () | |
| Games | 0 |
| Score | 0 |
| We | 0 |
| SWe | 0 |
| Temp +/- | 0 |
| Penalties | 0 |
| Weight perform | 0 |
| Final +/- | 0 |
| New Rating () | |
| Rating | 1200 |
| K-factor | 36 |
| Floor | 700 |
| Highest | 1200 (2024-02-01) |
| Min/Max +/- allowed | 165.8 |
Rating Graph
Tournaments
| # | Tournament | Type | Start | End | Host | Rounds | Rating | Games | Score | Perform | Rat+/- | Details |
| 1 | Overberg Schools Primary School Trials (Region 2) 2026 (U7 Mixed+U9 Boys) | Rapid | 2026-02-28 | 2026-02-28 | Overberg (WOS) | 5 | 1200.4 | 5 | 4 | 1473.2 | 34 | Details |
| # | Tournament | Type | Start | End | Host | Rounds | Rating | Games | Score | Perform | Rat+/- | Details |
| 1 | Overberg Schools Open Championship 2026 (U9) | Rapid | 2026-01-31 | 2026-01-31 | Overberg (WOS) | 6 | 1193.5 | 6 | 3 | 1239.8 | 0 | Details |
| 2 | Overberg Schools - PS Closed 2025 (U9 Boys) | Standard | 2025-03-08 | 2025-03-08 | Overberg (WOS) | 5 | 1203.4 | 5 | 2 | 1148.7 | 0 | Details |
| 3 | Overberg Schools - PS Trials (Region 2) 2025 (U9) | Rapid | 2025-02-15 | 2025-02-15 | Overberg (WOS) | 6 | 1191.8 | 6 | 4 | 1320.5 | 0 | Details |
| 4 | Curro Hermanus Summer Open 2025 (U9) | Rapid | 2025-02-08 | 2025-02-08 | Overberg (WOS) | 6 | 1191.8 | 6 | 3 | 1264.4 | 0 | Details |
| 5 | Overberg Schools & Federation Open 2025 (U9) | Rapid | 2025-02-01 | 2025-02-01 | Overberg (WOS) | 6 | 1191.8 | 6 | 2 | 1067 | 0 | Details |
| 6 | PR Booyse Standard Tournament 024 (Development) | Standard | 2024-11-02 | 2024-11-02 | West Coast (WCU) | 5 | 1184.3 | 5 | 2 | 1126 | 0 | Details |
| 7 | Western Cape PS Individuals Championship 2024 (U7 Boys) | Standard | 2024-05-04 | 2024-05-05 | West Coast (WCU) | 6 | 1234.2 | 6 | 2 | 996.6 | 0 | Details |
| 8 | West Coast Schools Chess Prestige Championships 2024 (U7) | Rapid | 2024-03-09 | 2024-03-09 | West Coast (WCU) | 5 | 1213 | 5 | 3.5 | 1372 | 0 | Details |
| 9 | Bo-Weskus Skole Prestige 2024 (O7) | Rapid | 2024-02-10 | 2024-02-10 | West Coast (WCU) | 5 | 1200 | 5 | 3 | 1285 | 0 | Details |
Game statistics ( )
| Games | 0 |
| Wins | 0 |
| Draws | 0 |
| Losses | 0 |
| White | 0 |
| Black | 0 |
| White wins | 0 |
| Black wins | 0 |
| Score | 0 |
| Percent | 0 |
| Dp | 0 |
| AOR | 0 |
| Performance | 0 |
Game statistics ()
| Games | 11 |
| Wins | 7 |
| Draws | 0 |
| Losses | 4 |
| White | 6 |
| Black | 5 |
| White wins | 4 |
| Black wins | 3 |
| Score | 7 |
| Percent | 63.6 |
| Dp | 115.9 |
| AOR | 1230 |
| Performance | 1345.9 |
Game statistics (History)
| Games | 55 |
| Wins | 27 |
| Draws | 3 |
| Losses | 25 |
| White | 28 |
| Black | 27 |
| White wins | 17 |
| Black wins | 10 |
| Score | 28.5 |
| Percent | 51.8 |
| Dp | 15.5 |
| AOR | 1209.2 |
| Performance | 1224.6 |
Rankings (Main)
| National | |
| Overall | 12699 |
| Gender | 9979 |
| Age group | 529 |
| Gender/Age | 381 |
| Provincial | |
| Overall | 3644 |
| Gender | 2788 |
| Age group | 215 |
| Gender/Age | 158 |
| Regional | |
| Overall | 429 |
| Gender | 324 |
| Age group | 14 |
| Gender/Age | 11 |
Rankings (Standard)
| National | |
| Overall | 12508 |
| Gender | 9463 |
| Age group | 677 |
| Gender/Age | 471 |
| Provincial | |
| Overall | 3565 |
| Gender | 2580 |
| Age group | 275 |
| Gender/Age | 196 |
| Regional | |
| Overall | 265 |
| Gender | 175 |
| Age group | 9 |
| Gender/Age | 8 |
Rankings (Rapid)
| National | |
| Overall | 3041 |
| Gender | 2444 |
| Age group | 123 |
| Gender/Age | 101 |
| Provincial | |
| Overall | 1255 |
| Gender | 989 |
| Age group | 67 |
| Gender/Age | 57 |
| Regional | |
| Overall | 271 |
| Gender | 193 |
| Age group | 10 |
| Gender/Age | 8 |
Rankings (Blitz)
| National | |
| Overall | -1 |
| Gender | -1 |
| Age group | -1 |
| Gender/Age | -1 |
| Provincial | |
| Overall | -1 |
| Gender | -1 |
| Age group | -1 |
| Gender/Age | -1 |
| Regional | |
| Overall | -1 |
| Gender | -1 |
| Age group | -1 |
| Gender/Age | -1 |
Performance ( )
| Games | 0 |
| Score | 0 |
| Percent | 0 |
| Aor | 0 |
| Dp | 0 |
| Prat | 0 |
Performance ()
| Games | 11 |
| Score | 7 |
| Percent | 63.6 |
| Aor | 1230 |
| Dp | 115.9 |
| Prat | 1345.9 |
Performance (12 months)
| Games | 16 |
| Score | 9 |
| Percent | 56.2 |
| Aor | 1231.2 |
| Dp | 53.1 |
| Prat | 1284.3 |
Performance (History)
| Games | 55 |
| Score | 28.5 |
| Percent | 51.8 |
| Aor | 1209.2 |
| Dp | 15.5 |
| Prat | 1224.6 |
Top 5 opponents most often played
| Type | # | Opponent | Games | White | Black | First tournament | Last tournament | Details |
| Overall | 1 | Henning, A (Alex) | 3 | 0 | 3 | Overberg Schools - PS Trials (Region 2) 2025 (U9) | Overberg Schools Primary School Trials (Region 2) 2026 (U7 Mixed+U9 Boys) | Details |
| Overall | 2 | Dube, Z (Zayne) | 3 | 2 | 1 | Overberg Schools - PS Trials (Region 2) 2025 (U9) | Overberg Schools Primary School Trials (Region 2) 2026 (U7 Mixed+U9 Boys) | Details |
| Overall | 3 | Van Wyk, L (Lara) | 2 | 1 | 1 | Bo-Weskus Skole Prestige 2024 (O7) | West Coast Schools Chess Prestige Championships 2024 (U7) | Details |
| Overall | 4 | Kuhn, D (Dian) | 2 | 1 | 1 | Overberg Schools & Federation Open 2025 (U9) | Curro Hermanus Summer Open 2025 (U9) | Details |
| Overall | 5 | Fourie, D (Duan) | 2 | 2 | 0 | West Coast Schools Chess Prestige Championships 2024 (U7) | Western Cape PS Individuals Championship 2024 (U7 Boys) | Details |
| Rapid | 1 | Henning, A (Alex) | 3 | 0 | 3 | Overberg Schools - PS Trials (Region 2) 2025 (U9) | Overberg Schools Primary School Trials (Region 2) 2026 (U7 Mixed+U9 Boys) | Details |
| Rapid | 2 | Van Wyk, L (Lara) | 2 | 1 | 1 | Bo-Weskus Skole Prestige 2024 (O7) | West Coast Schools Chess Prestige Championships 2024 (U7) | Details |
| Rapid | 3 | Faasen, C (Charles) | 2 | 0 | 2 | Overberg Schools & Federation Open 2025 (U9) | Curro Hermanus Summer Open 2025 (U9) | Details |
| Rapid | 4 | Kuhn, D (Dian) | 2 | 1 | 1 | Overberg Schools & Federation Open 2025 (U9) | Curro Hermanus Summer Open 2025 (U9) | Details |
| Rapid | 5 | Dube, Z (Zayne) | 2 | 2 | 0 | Overberg Schools - PS Trials (Region 2) 2025 (U9) | Overberg Schools Primary School Trials (Region 2) 2026 (U7 Mixed+U9 Boys) | Details |