Quick answer: an Olympic-distance race (1500 m swim, 40 km bike, 10 km run) at 2:00 per 100 m, 18 mph and 9:00 per mile, with 3:00 and 2:00 transitions, finishes in 2:53:46: swim 30:00, bike 1:22:51, run 55:55.
How to use it
Pick super sprint, sprint, Olympic, 70.3 or 140.6, or choose Custom and type each distance. Enter swim pace per 100 m or per 100 yd, T1, bike speed in mph or km/h, T2, and run pace per mile or km. The table shows each leg, the elapsed time after it and its share of the day, which tells you where an hour of training buys the most time.
Worked example: a full-distance race
The 140.6 is a 3.8 km swim (2.36 miles), 180 km bike (111.8 miles) and 42.2 km run. At 2:00 per 100 m the swim is 38 x 2:00 = 1:16:00. 180 km at 18 mph (28.97 km/h) is 6:12:49. A marathon at 11:00 per mile is 4:48:24. Add 5:00 for T1 and 3:00 for T2 and the finish is 12:25:14.
The formula
Swim = distance / 100 x pace per 100. Bike = distance / speed. Run = distance x pace. Finish = swim + T1 + bike + T2 + run. Every leg is kept to the second and rounded only for display.
Making the estimate realistic
Use paces you can hold for the whole leg, not your best pool or track numbers. Open water usually swims slower than the pool: sighting, wetsuits and currents all change it, and courses are rarely exact. Your bike speed on race day depends on the course profile and wind more than on any flat training loop. Running off the bike is slower than running fresh, especially in the first mile or two, so add a margin to your open run pace for long races.
Work out each input: the swim pace calculator for the swim and the pace calculator for the run.
Formula and examples checked . Found a problem? Tell us.
Questions
How long does an Olympic triathlon take?
It depends on your paces. At 2:00 per 100 m, 18 mph and 9:00 per mile with 5 minutes of transitions, it takes 2:53:46.
What are the triathlon distances?
Sprint: 750 m swim, 20 km bike, 5 km run. Olympic: 1500 m, 40 km, 10 km. 70.3 (half): 1.9 km, 90 km, 21.1 km. 140.6 (full): 3.8 km, 180 km, 42.2 km.
How do I estimate my Ironman time?
Enter your swim pace, bike speed and marathon pace for the 140.6 distance. At 2:00 per 100 m, 18 mph and 11:00 per mile with 8 minutes of transitions, the total is 12:25:14.
How long is a 70.3 bike leg in miles?
90 km, which is 55.9 miles.