Predict
10K time predictor
Your recent race
MetricSplit ladder
Equivalent efforts- 5K21:204:16 /km
Your entered race is marked; every other row is projected from it.
Worked example
A 21:21 5K projects to a 44:30 10K at 4:27/km. Doubling the distance costs about eleven seconds per kilometre for a runner with a normal endurance base.
Common questions
- How accurate is a 10K prediction from a 5K?
- Very reliable — the two distances are close enough that endurance base rarely distorts the projection. Most trained runners land within a minute.
- Can I predict a 10K from a marathon time?
- Yes, and it usually under-predicts. Marathon fitness carries plenty of endurance but not necessarily the speed a fast 10K needs, so treat the optimistic end as achievable with some sharpening.
- Why is my predicted pace slower than my 5K pace?
- Sustainable pace falls as distance rises. Riegel's 1.06 exponent turns a doubling of distance into roughly eleven seconds per kilometre.