Predict
5K time predictor
Your recent race
MetricSplit ladder
Equivalent efforts- 10K44:304:27 /km
Your entered race is marked; every other row is projected from it.
Worked example
A 44:30 10K projects to a 21:21 5K at 4:16/km. Halving the distance buys about eleven seconds per kilometre.
Common questions
- How accurate is a 5K prediction from a longer race?
- Reliable in the sense that the endurance is clearly there, but it tends to be conservative. A 5K also demands top-end speed that a marathon never tests, so the optimistic end is realistic if you have done any fast work.
- Why does a marathon predict a slower 5K than I can run?
- Equivalency assumes balanced training. Endurance-heavy runners usually beat their predicted 5K once they add intervals; speed-heavy runners usually miss their predicted marathon.
- Is the 5K a good input for predicting longer races?
- It is the weakest input for a marathon, because it tests almost none of the endurance a marathon exposes. Use the longest race you have run recently instead.