| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. Eliskases vs K Langeweg |
| 1-0 | 33 |
1959 |
Beverwijk | A14 English |
| 2. C B Van den Berg vs K Langeweg |
| ½-½ | 27 |
1959 |
Hoogovens | B90 Sicilian, Najdorf |
| 3. K Langeweg vs Larsen |
 | ½-½ | 46 |
1959 |
Hoogovens | A16 English |
| 4. Minev vs K Langeweg |
| 1-0 | 25 |
1960 |
Leipzig ol (Men) fin-A | E43 Nimzo-Indian, Fischer Variation |
| 5. J Marsalek vs K Langeweg |
| 1-0 | 42 |
1960 |
WchT U26 07th | D01 Richter-Veresov Attack |
| 6. K Langeweg vs Bisguier |
| 0-1 | 10 |
1961 |
Utrecht | D51 Queen's Gambit Declined |
| 7. K Langeweg vs Bobotsov |
| ½-½ | 48 |
1961 |
Zevenaar | E70 King's Indian |
| 8. C B Van den Berg vs K Langeweg |
| 0-1 | 35 |
1961 |
IBM | B96 Sicilian, Najdorf |
| 9. K Langeweg vs A Prameshuber |
| 1-0 | 60 |
1961 |
Clare Benedict Cup 08th | D41 Queen's Gambit Declined, Semi-Tarrasch |
| 10. K Langeweg vs C B Van den Berg |
| 1-0 | 31 |
1961 |
NED-ch20 | A22 English |
| 11. K Langeweg vs F Kuijpers |
| 1-0 | 41 |
1961 |
IBM | D37 Queen's Gambit Declined |
| 12. Minev vs K Langeweg |
| ½-½ | 30 |
1962 |
Varna ol (Men) fin-A | B25 Sicilian, Closed |
| 13. Schmid vs K Langeweg |
| 1-0 | 31 |
1962 |
Clare Benedict Cup 09th | B43 Sicilian, Kan, 5.Nc3 |
| 14. A Matanovic vs K Langeweg |
| ½-½ | 31 |
1962 |
Varna ol (Men) fin-A | B42 Sicilian, Kan |
| 15. K Langeweg vs Robatsch |
| 0-1 | 31 |
1962 |
Beverwijk | A21 English |
| 16. K Langeweg vs Filip |
| ½-½ | 22 |
1962 |
Reggio Emilia 6263 | A22 English |
| 17. K Langeweg vs I Bilek |
| 0-1 | 32 |
1962 |
Olympiad | A71 Benoni, Classical, 8.Bg5 |
| 18. K Langeweg vs Parma |
| ½-½ | 20 |
1962 |
Olympiad | E11 Bogo-Indian Defense |
| 19. Geller vs K Langeweg |
| 1-0 | 25 |
1962 |
Varna ol | A61 Benoni |
| 20. Hort vs K Langeweg |
| 1-0 | 28 |
1962 |
Varna | A34 English, Symmetrical |
| 21. Bisguier vs K Langeweg |
| 1-0 | 29 |
1962 |
Beverwijk | A48 King's Indian |
| 22. E Paoli vs K Langeweg |
| 0-1 | 47 |
1962 |
Reggio Emilia 6263 | B48 Sicilian, Taimanov Variation |
| 23. K Langeweg vs C B Van den Berg |
| 0-1 | 34 |
1962 |
IBM | E13 Queen's Indian, 4.Nc3, Main line |
| 24. L Zinn vs K Langeweg |
 | 0-1 | 40 |
1962 |
Varna ol (Men) fin-A | B43 Sicilian, Kan, 5.Nc3 |
| 25. K Langeweg vs Stahlberg |
| 0-1 | 17 |
1963 |
Hoogovens | A10 English |