| Event | Time | Meet | Date |
|---|---|---|---|
| 100m Breaststroke | 1:05.59 | 2025 Age Group International SC | 2025-11-27 |
| 100m Butterfly | 1:01.57 | 2025 Age Group International SC | 2025-11-27 |
| 100m Freestyle | 59.97 | ManSask Provincial Championships | 2025-07-10 |
| 100m Freestyle | 58.06 | The Steve Molloy Invitational 2025 | 2025-11-07 |
| 100m IM | 1:00.92 | 2025 Prairie Winter International | 2025-12-11 |
| 200m Breaststroke | 2:40.63 | ManSask Provincial Championships | 2025-07-10 |
| 200m Breaststroke | 2:23.68 | 2025 Age Group International SC | 2025-11-27 |
| 200m IM | 2:22.99 | ManSask Provincial Championships | 2025-07-10 |
| 50m Backstroke | 28.50 | 2025 Age Group International SC | 2025-11-27 |
| 50m Breaststroke | 31.44 | ManSask Provincial Championships | 2025-07-10 |
| 50m Breaststroke | 29.63 | 2025 Age Group International SC | 2025-11-27 |
| 50m Butterfly | 26.80 | 2025 Age Group International SC | 2025-11-27 |
| 50m Freestyle | 26.46 | ManSask Provincial Championships | 2025-07-10 |
| 50m Freestyle | 24.95 | 2025 Age Group International SC | 2025-11-27 |
Mendoza, Justin Nathan's top personal bests include 100m Breaststroke (1:05.59), 100m Butterfly (1:01.57), 100m Freestyle (59.97), 100m Freestyle (58.06), 100m IM (1:00.92).
Mendoza, Justin Nathan swims for Alpha Swim Club.
Mendoza, Justin Nathan has competed in 5 meets.