| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. J Karlsson vs A Grekh |
| 1-0 | 24 | 2009 | Cappelle Open | A07 King's Indian Attack |
| 2. J Karlsson vs P Petitcunot |
| 0-1 | 24 | 2009 | Cappelle Open | A01 Nimzovich-Larsen Attack |
| 3. J Karlsson vs B Eiholt |
 | 1-0 | 13 | 2009 | Politiken Cup | A09 Reti Opening |
| 4. M Antonsen vs J Karlsson |
| 1-0 | 37 | 2009 | Politiken Cup | E81 King's Indian, Samisch |
| 5. J Karlsson vs J H Nielsen |
| 1-0 | 35 | 2009 | Politiken Cup | A04 Reti Opening |
| 6. A S Rasmussen vs J Karlsson |
| 1-0 | 69 | 2009 | Politiken Cup | B06 Robatsch |
| 7. J Karlsson vs J Brorsen |
| 1-0 | 53 | 2009 | Politiken Cup | A04 Reti Opening |
| 8. R Burmeister vs J Karlsson |
| 1-0 | 40 | 2009 | Politiken Cup | B06 Robatsch |
| 9. J Karlsson vs I L Hansen |
| 1-0 | 74 | 2009 | Politiken Cup | B06 Robatsch |
| 10. J Pallesen vs J Karlsson |
| 0-1 | 44 | 2009 | Politiken Cup | E93 King's Indian, Petrosian System |
| 11. J Karlsson vs M Matthiesen |
| ½-½ | 82 | 2009 | Politiken Cup | B50 Sicilian |
| 12. D Kovachev vs J Karlsson |
| 0-1 | 119 | 2009 | Politiken Cup | B06 Robatsch |
| 13. J Karlsson vs P Nielsen |
| 1-0 | 36 | 2012 | Politiken Cup | A06 Reti Opening |
| 14. J Pallesen vs J Karlsson |
| 1-0 | 46 | 2012 | Politiken Cup | B07 Pirc |
| 15. J Karlsson vs E Arvidsson |
| ½-½ | 114 | 2012 | Politiken Cup | A05 Reti Opening |
| 16. J Karlsson vs F Borg |
| 1-0 | 25 | 2012 | Politiken Cup | A04 Reti Opening |
| 17. J Molvig vs J Karlsson |
| 0-1 | 22 | 2012 | Politiken Cup | E91 King's Indian |
| 18. J Karlsson vs F Andersen |
| 1-0 | 102 | 2012 | Politiken Cup | A04 Reti Opening |
| 19. A Thaler vs J Karlsson |
| 0-1 | 47 | 2012 | Politiken Cup | D70 Neo-Grunfeld Defense |
| 20. J Karlsson vs A Yusupov |
| 0-1 | 60 | 2013 | Gibraltar Masters | A13 English |
| 21. F Cebada Benitez vs J Karlsson |
| 0-1 | 50 | 2013 | Gibraltar Masters | A07 King's Indian Attack |
| 22. J Karlsson vs X Wemmers |
| 0-1 | 45 | 2013 | Gibraltar Masters | A04 Reti Opening |
| 23. C Nwachukwu vs J Karlsson |
| 0-1 | 69 | 2013 | Gibraltar Masters | B06 Robatsch |
| 24. J Karlsson vs M Godard |
| 0-1 | 60 | 2013 | Gibraltar Masters | A13 English |
| 25. P Obiamiwe vs J Karlsson |
| 1-0 | 40 | 2013 | Gibraltar Masters | E91 King's Indian |
Kibitzing
