Ironman Triathlon: Distances, Times and Training

Also called 140.6, Full distance, Long distance.

An Ironman is a 3.8 kilometre swim, a 180 kilometre bike and a 42.2 kilometre run, which is a full marathon. The three legs total 140.6 miles. Most finishers take between 12 and 15 hours, and races carry a 17 hour cut-off along with intermediate cut-offs for the swim and bike.

Distance breakdown

  • Swim: 3.8km (2.36 miles)
  • Bike: 180km (111.8 miles)
  • Run: 42.2km (26.2 miles)
  • Total: 226km (140.4 miles)

Typical finish times

  • Elite: Under 8 hours
  • Advanced: 10 to 12 hours
  • Intermediate: 12 to 14 hours
  • First-timer: 14 to 17 hours

Ranges, not targets. Course profile, heat and water conditions move every one of these on the day.

Training load

  • Weekly hours: 12 to 20 hours
  • Prep time: 24 to 30 weeks
  • Longest sessions
  • Swim: 75 to 90 minutes
  • Bike: 5 to 6 hours
  • Run: 2 hours 30 to 3 hours

Each leg of a ironman triathlon

The swim (3.8km)

An hour to an hour and 45 for most age-groupers, with a typical cut-off around 2 hours 20. It is a small fraction of your day in time terms, so the goal is to finish it efficiently and calmly rather than fast. Burning matches here shows up eleven hours later.

The bike (180km)

Five to seven and a half hours, and the longest single block of the day. Nutrition is not optional: you need a rehearsed hourly plan for carbohydrate, fluid and sodium. Almost every Ironman that unravels on the run unravelled on the bike first.

The run (42.2km)

A full marathon after eight or more hours of work, usually 4 to 6 hours. Very few age-groupers run it continuously, and a deliberate run-walk strategy through aid stations is a common and effective approach rather than a failure.

How it compares to the other distances

Standard triathlon distances compared by swim, bike, run and total
DistanceSwimBikeRunTotalTypical finish
Super Sprint400m10km2.5km12.9km (8 mi)45 to 60 minutes
Sprint750m20km5km25.75km (16 mi)1:15 to 1:30
Olympic1.5km40km10km51.5km (32 mi)2:30 to 3:00
Half Ironman1.9km90km21.1km113km (70.2 mi)5:15 to 6:15
Ironman3.8km180km42.2km226km (140.4 mi)12 to 14 hours

The typical finish column shows the intermediate band for each distance.

Who this distance suits

Athletes with a 70.3 finish behind them and the ability to protect 12 or more training hours a week for six months. The training commitment, not the race, is what most people underestimate.

  • The three legs total 140.6 miles
  • Typically a 17 hour overall cut-off, with intermediate swim and bike cut-offs
  • Needs 12 to 20 hours a week over six months or more
  • Nutrition is a rehearsed plan, not a race-day decision
  • Recovery takes weeks, and the training block dominates a season

Common questions

How long is an Ironman?

An Ironman is a 3.8 kilometre swim, a 180 kilometre bike and a 42.2 kilometre marathon, totalling 140.6 miles. The run leg is a full marathon distance.

How far is the Ironman swim?

The Ironman swim is 3.8 kilometres, about 2.4 miles. Most events set a swim cut-off around 2 hours 20 minutes, and athletes who miss it do not continue to the bike.

How long does an Ironman take?

Most finishers take 12 to 15 hours. Strong age-groupers finish in 10 to 12, and professionals go under 8. Races normally close 17 hours after the start, so a 7am start means a midnight cut-off.

How long should I train for an Ironman?

Six to eight months of structured training on 12 to 20 hours a week, assuming you already have a 70.3 finish and a solid aerobic base. Building that base first, before the plan starts, is what separates a finish from an injury.

Guides for this distance