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Race time predictor
Your predicted times
| Daniels (VDOT) | Riegel | Pace | |
|---|---|---|---|
| 5K | 24:06 | 23:59 | 4:49/km |
| 10K | 50:00 | 50:00 | 5:00/km |
| Half marathon | 1:50:52 | 1:50:19 | 5:15/km |
| Marathon | 3:49:34 | 3:50:01 | 5:26/km |
Your training paces · min/km
Your VDOT
40.0
Easy
6:11–6:49
Threshold
5:05
Marathon
5:26
Intervals
4:40
Repetitions
4:25
How it works
Daniels (VDOT): Jack Daniels and Jimmy Gilbert’s formula estimates the oxygen cost of your pace and the share of your VO₂max you can hold for the length of the effort. Their ratio is an index, the VDOT, from which a time at any distance and your training paces follow.
Riegel: Peter Riegel’s formula, T2 = T1 × (D2 / D1)^1.06, extrapolates a time from one distance to another with a single exponent. Simpler, it gets optimistic as the gap between distances grows.
What these numbers don’t tell you
A predicted time is what you could run with training suited to the distance, on a flat course, in cool weather. It knows nothing about hills, heat or how much you train. Use it to pick a goal, not as a promise. This content is for information only and does not replace the advice of a doctor or a coach.
A plan to beat this time
Kardioo starts from your real sessions, works out your paces and builds a plan that adjusts every week to what you actually did. The first week is free.
Coming soon