| 2258.3 | 2270.9 | 20 | 20 | Klaasen, CJ (Calvin John) | FM | WCT | 2199.7 | 2224.1 | Cape Gambit Invitational 2025 | 1 | 2025-04-18 | S | W | 0.5 | 0.61 | -0.11 | -2.2 | 0.6 | -0.1 | -2 |
| 2258.3 | 2267.4 | 20 | 20 | Klaasen, CJ (Calvin John) | FM | WCT | 2199.7 | 2184.8 | Hermanus Chess Club Open 2025 (Championship) | 3 | 2025-04-12 | R | W | 1 | 0.61 | 0.39 | 4.2 | 0.64 | 0.36 | 7.2 |
| 2273.6 | 2282.4 | 20 | 20 | Klaasen, CJ (Calvin John) | FM | WCT | 2195.2 | 2224.2 | Cape Town Masters Challenge 2025 (Masters) | 5 | 2025-01-08 | S | B | 0 | 0.55 | -0.55 | -11 | 0.53 | -0.53 | -10.6 |
| 2246.8 | 2260.7 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2204.8 | 2192.4 | Hermanus Chess Club Open 2024 (Championship) | 6 | 2024-04-20 | R | B | 0 | 0.51 | -0.51 | -4.8 | 0.54 | -0.54 | -10.8 |
| 2246.8 | 2261.7 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2204.8 | 2230.1 | South African Closed Chess Championship 2024 (Open) | 7 | 2024-03-30 | S | W | 0.5 | 0.59 | -0.09 | -1.8 | 0.58 | -0.08 | -1.6 |
| 2248 | 2257.4 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2209.5 | 2228.9 | Cape Town Masters Challenge 2024 (Masters) | 9 | 2024-01-07 | S | W | 0.5 | 0.59 | -0.09 | -1.8 | 0.57 | -0.07 | -1.4 |
| 2243 | 2275.2 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2162.9 | 2188.5 | 2023 Moja Chess Extravaganza (Prestige) | 4 | 2023-10-01 | S | W | 0.5 | 0.64 | -0.14 | -2.8 | 0.64 | -0.14 | -2.8 |
| 2253.6 | 2286 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2162.4 | 2190.3 | WP Club League 2023 (A) | 9 | 2023-09-02 | S | B | 0 | 0.56 | -0.56 | -11.2 | 0.57 | -0.57 | -11.4 |
| 2263.9 | 2292.4 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2189.4 | 2230.6 | GPCA Rapid 2023 (Championship) | 4 | 2023-06-24 | R | B | 1 | 0.54 | 0.46 | 5 | 0.53 | 0.47 | 9.4 |
| 2257.4 | 2281.2 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2187.7 | 2197.2 | Cape Town Masters Challenge 2023 (IM Norm) | 2 | 2023-01-04 | S | W | 0.5 | 0.62 | -0.12 | -2.4 | 0.64 | -0.14 | -2.8 |
| 2257.8 | 2272.2 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2189.1 | 2197.8 | 2022 Western Province Club League (Premier) | 9 | 2022-09-17 | S | B | 1 | 0.54 | 0.46 | 9.2 | 0.54 | 0.46 | 9.2 |
| 2285.1 | 2302.8 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2226.7 | 2237.9 | 2022 South African Closed Chess Championships (Open) | 5 | 2022-05-10 | S | B | 1 | 0.53 | 0.47 | 9.4 | 0.53 | 0.47 | 9.4 |
| 2297.1 | 2317.8 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2198.3 | 2212.4 | 2020 Cape Of Good Hope Open (Elite) | 4 | 2020-02-22 | S | W | 1 | 0.66 | 0.34 | 5.9 | 0.66 | 0.34 | 6.8 |
| 2311.9 | 2336.3 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2228.6 | 2239.6 | 2019 South African Closed Chess Championships (Open A) | 6 | 2019-12-12 | S | B | 0.5 | 0.56 | -0.06 | -1.2 | 0.57 | -0.07 | -1.4 |
| 2315.4 | 2340.7 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2243.8 | 2255.8 | 2019 Western Province League (Premier) | 9 | 2019-08-24 | S | B | 0.5 | 0.54 | -0.04 | -0.8 | 0.56 | -0.06 | -1.2 |
| 2349.1 | 2347.5 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2253 | 2245.8 | Stellenberg Youth Chess Championship 2019 (Presige) | 4 | 2019-05-01 | R | W | 0 | 0.65 | -0.65 | -7.8 | 0.66 | -0.66 | -13.2 |
| 2349.1 | 2349.7 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2253 | 2257 | 2019 Western Province Open (Elite) | 3 | 2019-05-25 | S | B | 0 | 0.57 | -0.57 | -9.9 | 0.57 | -0.57 | -11.4 |
| 2351.1 | 2352.8 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2248.2 | 2261.2 | ACL Open 2018 (Elite) | 3 | 2018-12-08 | S | W | 0.5 | 0.66 | -0.16 | -3.2 | 0.65 | -0.15 | -3 |
| 2352.8 | 2350.3 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2260.8 | 2241.3 | Graham Solomon Memorial 2018 (Blitz) | 8 | 2018-11-25 | B | B | 0 | 0.57 | -0.57 | -2.8 | 0.59 | -0.59 | -11.8 |
| 2352.5 | 2352 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2231.2 | 2231.6 | 2018 Western Province League (Premier) | 3 | 2018-08-11 | S | B | 1 | 0.6 | 0.4 | 8 | 0.6 | 0.4 | 8 |
| 2361.8 | 2346.9 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2263.1 | 2258.4 | Eldo Smart Memorial Rapid Tournament 2018 | 7 | 2018-06-16 | R | B | 1 | 0.57 | 0.43 | 4 | 0.56 | 0.44 | 8.8 |
| 2350 | 2348.4 | 20 | 20 | Klaasen, CJ (Calvin) | FM | WCT | 2251.4 | 2253.6 | 2018 Capablanca RR (GM Norm) | 1 | 2018-04-26 | S | W | 1 | 0.66 | 0.34 | 6.8 | 0.65 | 0.35 | 7 |
| 2315 | 2315 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2247 | 2247 | 2017 South African Closed Chess Championships (Open) | 6 | 2017-12-14 | S | W | 0.5 | 0.59 | -0.09 | -1.8 | -0.09 | 0.59 | 11.8 |
| 2315 | 2315 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2236 | 2236 | Gpca - Pitt Memorial 2017 (Elite) | 4 | 2017-10-28 | S | B | 0.5 | 0.61 | -0.11 | -2.1 | -0.11 | 0.61 | 12.2 |
| 2322 | 2322 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2218 | 2218 | 2017 National Club Championships (A) | 5 | 2017-09-25 | S | B | 0.5 | 0.64 | -0.14 | -2.8 | -0.14 | 0.64 | 12.8 |
| 2322 | 2322 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2218 | 2218 | 2017 Western Province League (Premier) | 3 | 2017-08-05 | S | B | 0 | 0.64 | -0.64 | -12.8 | -0.64 | 0.64 | 12.8 |
| 2361 | 2361 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2188 | 2188 | Cape Town Heritage Chess Festival 2017 (Elite) | 4 | 2017-03-24 | S | B | 1 | 0.73 | 0.27 | 5.4 | 0.27 | 0.73 | 14.6 |
| 2349 | 2349 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2193 | 2193 | Cape Of Good Hope Open 2017 (A) | 5 | 2017-01-29 | S | W | 1 | 0.71 | 0.29 | 5 | 0.29 | 0.71 | 14.2 |
| 2336 | 2336 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2160 | 2160 | 2016 African Chess Lounge (Im Norm) | 4 | 2016-11-29 | S | W | 1 | 0.73 | 0.27 | 5.4 | 0.27 | 0.73 | 14.6 |
| 2310 | 2310 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2113 | 2113 | Sa Closed 2015 (Open A) | 6 | 2015-12-17 | S | W | 0 | 0.75 | -0.75 | -15 | -0.75 | 0.75 | 15 |
| 2316 | 2316 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2113 | 2113 | Western Province League 2015 (Premier) | 2 | 2015-07-25 | S | W | 1 | 0.76 | 0.24 | 4.8 | 0.24 | 0.76 | 15.2 |
| 2315 | 2315 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2109 | 2109 | Wp Open Chess Championship 2015 (Elite-Section) | 5 | 2015-08-09 | S | B | 0.5 | 0.76 | -0.26 | -5.2 | -0.26 | 0.76 | 15.2 |
| 2302 | 2302 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2113 | 2113 | South African Open 2015 (A) | 8 | 2015-07-08 | S | B | 1 | 0.75 | 0.25 | 5 | 0.25 | 0.75 | 15 |
| 2340 | 2340 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2141 | 2141 | Cape Town International Classic (Invitational) | 5 | 2015-03-26 | S | W | 1 | 0.76 | 0.24 | 4.8 | 0.24 | 0.76 | 15.2 |
| 2357 | 2357 | 20 | 20 | Klaasen, Cj (Calvin) | | WP | 2127 | 2127 | Manyanani Chess Festival 2014 Prestige Section | 4 | 2014-06-15 | S | B | 0 | 0.79 | -0.79 | -15.8 | -0.79 | 0.79 | 15.8 |
| 2332 | 2332 | 20 | 20 | Klaasen, Cj (Calvin) | | WP | 2127 | 2127 | Cape Of Good Hope Open 2014 (Prestige Section) | 5 | 2014-02-02 | S | B | 1 | 0.76 | 0.24 | 4 | 0.24 | 0.76 | 15.2 |
| 2342 | 2342 | 20 | 20 | Klaasen, Cj (Calvin) | | WP | 2124 | 2124 | South African Closed 2014 (Open A) | 8 | 2014-01-10 | S | W | 0.5 | 0.78 | -0.28 | -5.6 | -0.28 | 0.78 | 15.6 |
| 2329 | 2329 | 20 | 20 | Klaasen, Cj (Calvin) | FM | WP | 2141 | 2141 | Manyanani Open 2013 (Open) | 5 | 2013-06-17 | S | B | 1 | 0.74 | 0.26 | 4.9 | 0.26 | 0.74 | 14.8 |
| 2349 | 2349 | 20 | 20 | Klaasen, Cj (Calvin) | NM | WP | 2151 | 2151 | South African Open Chess Championship 2012 (Open) | 6 | 2012-07-03 | S | B | 1 | 0.76 | 0.24 | 4.8 | 0.24 | 0.76 | 15.2 |
