Cassie O'Byrne

IrelandIrelandActive
Born
Apr 23, 2008 (18 years old)
Events
400 Metres Short Track · 300 Metres

Cassie O'Byrne is a Ireland sprinter, born on April 23, 2008. She competes primarily in the 200m, 400m and 400m.

Her personal bests include 25.06 in the 200m, 56.95 in the 400m, 56.17 in the 400m, 56.17 in the 400m-short-track and 25.37 in the 200m-short-track. She is currently active on the international athletics circuit, representing Ireland.

Personal best · 400 Metres Short Track56.17
2026 season best56.17Feb 14, 2026 · AIT International Arena, Athlone (IRL) (i)
2026 season best
Personal best · 300 Metres39.92
Last competitionNational League FinalAug 9, 2026 · 58.24
National League Final

As of Nov 14, 2026: 400 Metres Short Track 56.17, 300 Metres 39.92, 2026 season best 56.17 (Feb 14, 2026, AIT International Arena, Athlone (IRL) (i)) · Last competition: National League Final, Aug 9, 2026, 58.24 · 18 years old

Personal bests

WA points calculator →
DisciplineResultAll-time2026
200mTullamore 2025Ireland 200 m all-time list25.06936 pts––
400mTullamore 2026Ireland 400 m all-time list56.95943 pts––
400mIndoorAthlone 202656.171,005 pts–#835
400m-short-trackIndoorAthlone 202656.171,005 pts––
200m-short-trackIndoorAthlone 202625.37960 pts––
300mDublin 202439.92962 pts––

Progression

SeasonDisciplineResultWindDateCompetitions
2026200m 24.78+2.8May 18, 2026Leinster Schools Track & Field Championships
2026200m Indoor24.78+2.8May 18, 2026Leinster Schools Track & Field Championships
2026200m-short-track Indoor25.37–Feb 15, 2026Leinster U12 - U19 Juvenile Indoor Championships
2026400m-short-track Indoor56.17–Feb 14, 2026Leinster U12 - U19 Juvenile Indoor Championships
2026400m Indoor56.95–Jul 4, 2026Irish U20 Championships
2026400m 56.95–Jul 4, 2026Irish U20 Championships
20264x200Metre Indoor1:45.95–Feb 1, 2026Leinster U12 - U19 Juvenile Indoor Championships Day 2
2025200m 25.06+0.8Jul 12, 2025National Juveniles Day 3 & 4 U18
FAQ

Frequently asked questions

Cassie O'Byrne's 400 Metres Short Track personal best is 56.17, set on Feb 14, 2026 in AIT International Arena, Athlone (IRL) (i).

Cassie O'Byrne competes in the 400 Metres Short Track and 300 Metres.

2026 season best: 56.17, set on Feb 14, 2026 in AIT International Arena, Athlone (IRL) (i). Last competition: National League Final on Aug 9, 2026, 58.24.