| Game |
| Result | Moves |
Year | Event/Locale | Opening |
| 1. Bethany Robinson vs J Ostensson |
| 0-1 | 30 | 2022 | Kvika Reykjavik Open | A01 Nimzovich-Larsen Attack |
| 2. J Ostensson vs Raj Jaivardhan |
| 0-1 | 40 | 2022 | Kvika Reykjavik Open | B23 Sicilian, Closed |
| 3. Guy Vernon vs J Ostensson |
| 1-0 | 26 | 2022 | Kvika Reykjavik Open | B90 Sicilian, Najdorf |
| 4. J Ostensson vs G F Briem |
| ½-½ | 44 | 2022 | Kvika Reykjavik Open | A07 King's Indian Attack |
| 5. William Sundberg vs J Ostensson |
| 0-1 | 36 | 2022 | Kvika Reykjavik Open | B00 Uncommon King's Pawn Opening |
| 6. J Ostensson vs M Ruiz Buendia |
| 0-1 | 49 | 2022 | Kvika Reykjavik Open | B23 Sicilian, Closed |
| 7. R Kracht vs J Ostensson |
| 1-0 | 13 | 2022 | Kvika Reykjavik Open | B21 Sicilian, 2.f4 and 2.d4 |
| 8. J Ostensson vs Grimur Danielsson |
| ½-½ | 41 | 2022 | Kvika Reykjavik Open | A07 King's Indian Attack |
| 9. A Banerjee vs J Ostensson |
| 0-1 | 28 | 2022 | Kvika Reykjavik Open | E73 King's Indian |
| 10. J Ostensson vs B Amin |
 | 0-1 | 18 | 2023 | Swedish Blitz Championship | C47 Four Knights |
| 11. K Ricken vs J Ostensson |
| ½-½ | 43 | 2023 | Reykjavik Open | A05 Reti Opening |
| 12. A Cramling Bellon vs J Ostensson |
| ½-½ | 26 | 2023 | Reykjavik Open | E71 King's Indian, Makagonov System (5.h3) |
| 13. J Ostensson vs M Zhezhovska |
| 0-1 | 41 | 2023 | 24th European Teams Women | B30 Sicilian |
| 14. S Norlamo vs J Ostensson |
| 0-1 | 42 | 2023 | 24th European Teams Women | E73 King's Indian |
| 15. H Thorsteinsdottir vs J Ostensson |
| 1-0 | 53 | 2023 | 24th European Teams Women | B42 Sicilian, Kan |
| 16. S Hryzlova vs J Ostensson |
| 1-0 | 35 | 2023 | 24th European Teams Women | A45 Queen's Pawn Game |
| 17. J Ostensson vs A Kalaiyalahan |
| ½-½ | 48 | 2023 | 24th European Teams Women | B31 Sicilian, Rossolimo Variation |
| 18. J Ostensson vs Nitin Vekhande Kshatriya |
| 0-1 | 39 | 2024 | Sitges Open-A | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 19. D Stevanic vs J Ostensson |
| ½-½ | 40 | 2024 | Sitges Open-A | B22 Sicilian, Alapin |
| 20. J Ostensson vs Gyaneshwar Boda |
| ½-½ | 27 | 2024 | Sitges Open-A | B51 Sicilian, Canal-Sokolsky (Rossolimo) Attack |
| 21. Sengupta Srijak vs J Ostensson |
| ½-½ | 25 | 2024 | Sitges Open-A | A39 English, Symmetrical, Main line with d4 |
| 22. J Ostensson vs L Lau |
| 0-1 | 46 | 2024 | Sitges Open-A | C44 King's Pawn Game |
| 23. G Elashvili vs J Ostensson |
| 1-0 | 13 | 2024 | Sitges Open-A | E64 King's Indian, Fianchetto, Yugoslav System |
| 24. J Ostensson vs A Ruiz Soria |
| 1-0 | 28 | 2024 | Sitges Open-A | D30 Queen's Gambit Declined |
| 25. U Bergaretxe Gavalda vs J Ostensson |
| 1-0 | 44 | 2024 | Sitges Open-A | E64 King's Indian, Fianchetto, Yugoslav System |
Kibitzing
