Triathlon calculator: your total time from sprint to Ironman
The total time of a triathlon is the sum of five parts: the swim (distance / 100 x pace per 100), transition 1, the bike (distance / speed), transition 2 and the run (distance x pace per km). Choose the format, enter your paces and transitions, and the tool gives you each part and your finish time.
Fill in the fields to see the result.
How to use it
- Choose the format: sprint, Olympic distance, 70.3 or Ironman.
- Enter your swim pace per 100, your average bike speed and your running pace per km (or per mile).
- Enter your two transitions: T1 (swim to bike) and T2 (bike to run).
- Read the time for each part and the total, then tweak one pace to see what it changes.
The method
The distances are those of the official formats: sprint, 750 m swim, 20 km bike and 5 km run; Olympic distance, 1.5 km, 40 km and 10 km, according to World Triathlon rules; 70.3: 1.9 km, 90 km and 21.1 km; Ironman: 3.8 km, 180 km and 42.2 km (or 2.4, 112 and 26.2 miles). The calculation is an addition: the swim time is the number of 100 m multiplied by your pace per 100, the bike time is the distance divided by your speed, the run time is the number of km multiplied by your pace, and you add the two transitions.
What makes the exercise useful is seeing the weight of each sport. The bike takes up the biggest share of race time, and Bentley et al. (2002) point out that it affects the run that follows. On an Olympic distance race, going from 32 to 33 km/h saves about 2:16, while swimming 5 seconds faster per 100 saves only 1:15.
An example
On an Olympic distance race: you swim at 1:50 per 100 m, so 15 x 1:50 = 27:30. T1 in 2:00. You ride at 32 km/h, so 40 / 32 = 1:15:00. T2 in 1:00. You run at 5:00 per km, so 10 x 5:00 = 50:00. Your total time is 27:30 + 2:00 + 1:15:00 + 1:00 + 50:00 = 2:35:30.
Limitations
The calculation assumes you hold in the race the paces you entered, and that's rarely the case if you take them from training: in triathlon, you run after riding, and your running pace is often slower than in training, especially at 70.3 and Ironman distance. Open water swimming (sighting, swell, mass start, wetsuit or not) isn't like swimming in a pool. Wind, the elevation of the bike course and heat change times a lot, and the calculator doesn't see them. Real distances also vary from one race to another, in Europe as in the United States, especially for sprints: check your race's course. Before a first 70.3 or Ironman, a medical checkup is a good idea.
Frequently asked questions
What are the distances of a triathlon?
Sprint: 750 m, 20 km, 5 km. Olympic: 1.5 km, 40 km, 10 km. 70.3: 1.9 km, 90 km, 21.1 km. Ironman: 3.8 km, 180 km, 42.2 km.
How much time should you plan for transitions?
It depends on the format and the size of the transition area. The simplest way: time a transition in training, then add a margin for race day, when the transition area is often bigger and the wetsuit takes longer to get off.
What running pace should you plan for after the bike?
A bit slower than your pace over the same distance in a standalone running race, and more so the longer the format. Train with bike-to-run sessions (bricks) to find out.
What's the difference between a 70.3 and an Ironman?
The 70.3 is a half Ironman: 70.3 miles in total (113 km), versus 140.6 miles (226 km) for the Ironman. All three distances are cut in half.
Sources
- World Triathlon (2025). Competition Rules. World Triathlon.
- Bentley D.J., Millet G.P., Vleck V.E., McNaughton L.R. (2002). Specific aspects of contemporary triathlon: implications for physiological analysis and performance. Sports Medicine, 32(6), 345-359.
What if ELYO worked it out for you?
ELYO reads your swim, bike and run workouts from your watch, works out your paces, zones and training load in all three sports, and adjusts your plan toward your triathlon.