| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Backstroke | 1:05.65 | 2026 OUA Swimming Championships | 2026-02-19 |
| 100m Butterfly | 1:07.55 | Toronto Grand Prix | 2026-01-24 |
| 100m Butterfly | 1:02.21 | 2026 OUA Swimming Championships | 2026-02-19 |
| 200m Backstroke | 2:31.02 | Tuesday Night at the Races - Thursday Edition | 2025-06-19 |
| 50m Backstroke | 29.65 | 2026 OUA Swimming Championships | 2026-02-19 |
| 50m Breaststroke | 38.36 | Birthday Cake Time Trial | 2025-05-31 |
| 50m Butterfly | 29.22 | Toronto Grand Prix | 2026-01-24 |
| 50m Butterfly | 27.86 | 2026 U SPORTS Swimming Championships | 2026-03-12 |
| 50m Freestyle | 28.81 | Toronto Grand Prix | 2026-01-24 |
| 50m Freestyle | 27.39 | Tuesday Night at the Races - Thursday Edition | 2025-06-19 |
Olivia Johnson's top personal bests include 100m Backstroke (1:05.65), 100m Butterfly (1:07.55), 100m Butterfly (1:02.21), 200m Backstroke (2:31.02), 50m Backstroke (29.65).
Olivia Johnson swims for Western University.
Olivia Johnson has competed in 7 meets.