As swimming is by far my weakest discipline, I always like to know where I would have been in a triathlon race if I were a better swimmer. Since I am now getting into longer triathlon distances, it is a perfect time for me to analyze the swim times of Ironman races.

The average swim time across Ironman races is 1h19 min (pace of 2:04 min/100m). The women are covering the 3,8 km in 1h22 min (or 2:10 min/100m) and the men in 1h18 min (or 2:03 min/100m).

Where pros are regularly swimming under the 50 minutes mark (or 1:19 min/100m), 25% of age-group triathletes are swimming under 1h09 min (or 1:49 min/100m) and 75% under 1h27 min (or 2:17 min/100m).

Those times are highly dependant on the course (lake vs. ocean vs. river) and on the allowance of wetsuits. Let’s check that in more detail.

METHODOLOGY

  • I checked all Ironman races from 2019, and I excluded the ones which were shortened. The final database is consisting of 58,720 swim times from age-groupers and 759 swim times from pro triathletes.
    A special thanks to Coach Cox, who is gathering results of all Ironman (as well as Ironman 70.3) events. He made my life easier!
  • For each race, I have checked the course profile on the Ironman website and classified it into either lake, river, or ocean.
  • I have looked at the pictures of each race from the 2019 event to confirm if wetsuits were allowed or not on this particular day.

AVERAGE IRONMAN SWIM TIME PER AGE GROUP

As you can see in the graph below, the average pace of women triathletes is really close to the men. It oscillates between 5 to 8 seconds per 100 m, translating to only 3 to 5 min of difference over the entire swim distance.

Average Ironman swim pace per Age group and gender

The average Ironman swim time for women is 1h22 min (or 2:10 min/100m). Only 25% of the women triathletes swam under 1h12 min (or 1:54 min/100m) and 75% under 1h29 min (or 2:20 min/100m).

The average Ironman swim time for men is 1h18 min (or 2:03 min/100m). Only 25% of the men triathletes swam under 1h09 min (or 1:49 min/100m) and 75% under 1h25 min (or 2:15 min/100m).

WHAT ARE THE FASTEST IRONMAN SWIM RACES (WITH WETSUIT)?

Looking at races where wetsuits were allowed, Ironman Australia was the fastest swim race with an average time of 1h10 min. The slowest one is IM Wisconsin with 1h28 min.

You can find below the average time for all races:

Average Ironman Swim Time in a lake with wetsuit
Average Ironman Swim Time in an ocean with wetsuit
Average Ironman Swim Time in a river with wetsuit

WHAT ARE THE FASTEST IRONMAN SWIM RACES (WITHOUT WETSUIT)?

Only 6 Ironman races were non-wetsuits in 2019. Chattanooga and Cozumel are pretty well known for being current assisted, so it is not surprising to see really fast times here (1h12 min).

After those two comes the World Championship race. With the best age groupers on the planet, the average swim time in Kona was an impressive 1h13 min (or 1:55 min/100m). It is 6 min faster than the swim races which allowed wetsuits!

You can find below the average time for all races:

Average Ironman Swim Time without wetsuit

WHAT IS THE SWIM CUT OFF TIME FOR AN IRONMAN?

The swim cut-off time for an Ironman is generally 2 hours and 20 min. The countdown starts when the last triathlete enters the water. However, the race officials can disqualify any swimmer who exceeds this 2h20 min based on their chip time.

You would need to swim slower than 3:41 min/100m to exceed this time. If you want to learn more about the cut-off times, check this article: Ironman Time Limits Per Sport And Per Race

Concluding I can say that on the one hand, I am really impressed by the fast swim times. On the other hand, seeing the cut-off time of 2h20 min still gave me some hope that with a decent amount of training, an Ironman swim is totally feasible.

If you enjoyed this analysis, have a look at those two articles which cover the bike and run legs of Ironman races: