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70.3 Worlds — Rolldown

Since the 2026 qualifying cycle, every 70.3 race runs two separate allocations, one for men and one for women, each with its own slot count. Within each, age-group winners get an automatic slot (rolling to 2nd and 3rd), and the rest form a performance pool that rolls down that gender's age-graded list. IRONMAN publishes the slot counts and age-grade factors but not how deep each rolldown went; this page replays every race's two rolldowns against who actually showed up at the championship. Numbers are estimates — method and limits at the bottom.

Races

Each race has a men's pool and a women's pool. Click a race for what every age group needed.

Method

How the rolldown is reconstructed

IRONMAN publishes each race's slot count for men and for women, and the age-grade factor for every age group. What it doesn't publish is who accepted. But every result carries a stable athlete id, so each qualifying race's finishers can be matched against the championship results: anyone in the championship field (including those who didn't start) took a slot somewhere.

Races are replayed in date order across the cycle, with the men's and women's allocations run separately. In each: age-group automatic slots go to the first of the top three who is in the championship field; an automatic slot none of them took joins that gender's performance pool; the pool then walks down that gender's age-graded list (finish time × factor), giving a slot to each championship athlete it meets, until it's full. An athlete takes the first slot they're offered and declines every later one — which is what keeps a serial racer from being counted at every race they entered. The cutoff is the last place the pool reached.

Men's and women's age-graded times aren't on the same scale — each gender is graded against its own fastest age group — so compare a men's cutoff with other men's cutoffs, not with a women's one.

Known biases, pulling in opposite directions:

  • Only North American races are in this dataset. Someone who qualified in Europe earlier in the cycle looks like they accepted here, filling the pool early — cutoffs look faster than they were.
  • Someone who accepted but has no championship result looks like they declined, so the pool fills later — cutoffs look slower.
  • Errors compound late in the cycle: an athlete wrongly assigned to an earlier race isn't available to the race that really qualified them. Fill rates fall in June for this reason.
  • A race run on a modified course is flagged; its times don't compare with anything else.

Checked against one known case: an M40-44 athlete at Santa Cruz 2025 who was offered a rolldown slot at 4:38:53, with athletes behind them also offered one. The simulation puts that age group's cutoff at 4:42:14 and has six championship athletes between that athlete and the end of the men's rolldown.