Which age group am I in, and how old must I be for each distance?

Age groups: age-group athletes race against others of the same gender in five-year bands, such as 25-29 or 30-34. Under World Triathlon rule 2.5, your age is your age on 31 December of the year of the race. So if you turn 30 at any point in 2026, you race in the 30-34 category for all of 2026.

Minimum ages for triathlon (World Triathlon Appendix A):

Elite or age-group: Triathlon South Africa separates elite athletes, who race internationally, from age-group athletes, who are non-professionals grouped by age.