A worked example
42.195 km at 5:30/km takes 3:52:04.35, displayed as 3:52:04 after rounding to a second.
Estimate elapsed time from a constant pace and distance. Includes 5K, 10K, half-marathon and marathon presets.
Start with the example, then make it your own. Results update as you type.
Finish time = distance in km × pace in seconds per km. One mile = 1.609344 km.
Projected finish time
3:52:04This is a constant-pace projection, not a prediction of fitness or race performance. The pace input is always minutes and seconds per kilometre, even when the distance is entered in miles.
Finish time = distance in km × pace in seconds per km. One mile = 1.609344 km.
42.195 km at 5:30/km takes 3:52:04.35, displayed as 3:52:04 after rounding to a second.
This is a constant-pace projection, not a prediction of fitness or race performance. The pace input is always minutes and seconds per kilometre, even when the distance is entered in miles.
No. Calculations run locally in your browser. The host still receives normal requests for website pages and assets.
Export a CSV, or use Print / PDF and choose Save as PDF in your browser. Inputs are not saved between visits.
No sign-up, paid API or subscription is required. Both language versions use the same calculation logic.
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