Triathlon Time Calculator

Projecting a finish time across the swim, bike, and run lets you plan a triathlon with intent rather than hope, whether you're lining up for a Sprint or chasing an Ironman. Feed in the paces you expect to hold and you get a full picture of race day, which makes it easy to see how a faster bike leg or a steadier run would move your overall number. That kind of forecast is what separates a rehearsed race from a reactive one.

Each leg's time comes from the pace you enter and the race distance: swim time = swim distance ÷ 100 × your minutes per 100 m, bike time = bike distance in miles ÷ your speed in mph, and run time = run distance in miles × your minutes per mile. The race presets are Sprint (750 m, 20 km, 5 km), Olympic (1,500 m, 40 km, 10 km), Half Ironman (1,900 m, 90 km, 21.1 km) and Ironman (3,800 m, 180 km, 42.2 km). The total then adds the legs and the two transitions: Total Finish Time = Swim + T1 + Bike + T2 + Run. T1 and T2 start at 3 and 2 minutes for every distance; change them to the times you actually expect. As long as your effort holds steady across the legs, this gives a dependable estimate.

The forecast is only as good as the assumptions behind it. Weather, a hilly course, or a dropped chain can all pull your real time away from the projection, so build in a buffer for the unexpected. Transitions are where many athletes lose time they never accounted for, and a few stray minutes in T1 and T2 add up quickly. Anchor your target splits to your actual fitness and racing experience rather than your best-case fantasy.