| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Backstroke | 1:21.52 | Icebreaker Invitational | 2026-01-30 |
| 100m Breaststroke | 1:39.92 | Bluefins Fall Pentathlon | 2025-11-14 |
| 100m Butterfly | 1:36.86 | Bluefins Fall Pentathlon | 2025-11-14 |
| 100m Freestyle | 1:08.50 | Winter Waves Invitational | 2026-03-13 |
| 200m Freestyle | 2:29.34 | Icebreaker Invitational | 2026-01-30 |
| 200m IM | 3:01.45 | Icebreaker Invitational | 2026-01-30 |
| 400m Freestyle | 5:16.12 | Winter Waves Invitational | 2026-03-13 |
| 50m Backstroke | 36.22 | Winter Waves Invitational | 2026-03-13 |
| 50m Butterfly | 35.47 | Winter Waves Invitational | 2026-03-13 |
| 50m Freestyle | 30.12 | Winter Waves Invitational | 2026-03-13 |
| 800m Freestyle | 10:58.45 | Winter Waves Invitational | 2026-03-13 |
Grandy, Jonah's top personal bests include 100m Backstroke (1:21.52), 100m Breaststroke (1:39.92), 100m Butterfly (1:36.86), 100m Freestyle (1:08.50), 200m Freestyle (2:29.34).
Grandy, Jonah swims for St. John's Legends Swim Club.
Grandy, Jonah has competed in 4 meets.