Triathlon pace calculator

How your triathlon time adds up

A triathlon finish time is the sum of five splits:

Finish = swim + T1 + bike + T2 + run

• Swim = (swim distance ÷ 100) × your pace per 100 m
• Bike = bike distance ÷ your average speed
• Run = run distance × your pace per kilometre
• T1 and T2 are your transition times, from the swim exit to riding, and from dismount to running

The calculator does this for every common distance and for any custom race. It is part of the free LeCoach cycling and running calculators.

Triathlon distances

Courses vary. Check your race's exact distances and use the custom option if they differ.

Getting realistic inputs

The calculator is only as good as the numbers you enter. The most common error is using your fresh, standalone pace for every leg.

Swim. Use your open-water race pace, not your pool pace. Open water is usually slower because of sighting, navigation and the start, although a wetsuit makes you faster. A pool pace plus 5 to 10 seconds per 100 m is a sensible start for most age-groupers.

Bike. Do not guess a speed. Work it out from the power you can hold for the distance in the cycling speed calculator, with your position and the course gradient. As a guide, many athletes hold 80 to 90 % of FTP for a sprint or standard distance, about 75 to 80 % for half distance and 65 to 75 % for full distance. Riding harder than that is the most common way to ruin the run.

Run. Your run off the bike is slower than a standalone run. Expect roughly 5 to 10 % slower for shorter races and 10 to 20 % slower for long-distance races, compared with your open 10K or half marathon pace. Use the race time predictor for your standalone pace, then add the margin.

Transitions. Typical age-group transitions are 1 to 3 minutes for T1 (including the run from the water) and 1 to 2 minutes for T2. At large events with long transition zones, T1 can be 5 minutes or more. Practise them; they are the cheapest time you will ever save.

Where the time goes

The bike is usually about half of your total time and the run about a third, which is why both get most of the training attention. The swim is the shortest split, but a bad swim costs energy that shows up later. For long races, nutrition on the bike decides much of the run. Plan it with the race nutrition calculator.

Common mistakes

• Adding up your best standalone times. You cannot swim, ride and run all at your fresh best in one race.
• Overcooking the bike. Ten minutes saved on the bike can cost twenty on the run.
• Ignoring the course. A hilly bike or a hot run changes everything. Adjust speed and pace for the conditions.
• Forgetting transition distance. Long transition areas add minutes that do not show up in the swim or bike splits.
• Underestimating fuel. In half and full distance races, running out of carbohydrate in the second half of the run is the single biggest cause of slowing.

When to adjust your plan

• Wetsuit or not. A non-wetsuit swim can be several minutes slower over 1,500 m.
• Heat. Lower your run pace by 5 to 10 % or more on hot days, and drink more on the bike.
• Wind on the bike. A windy course makes a fixed power target more useful than a speed target.
• First race at a distance. Be conservative. Finishing strong is the goal; the time will come next season.

Use the race day checklist with the triathlon option to pack everything from goggles to elastic laces.

LeCoach coaches the bike and the run from your own power and pace data in Intervals.icu, so the two longest splits of your race get the structured training they need.