UTMB Finish Time Predictor
UTMB race stats pre-loaded (171km, 10,000m D+). Enter a known race result to get an elevation-adjusted UTMB finish time estimate.
Predict your UTMB finish time from a reference race result, adjusted for the course's 171 km and roughly 10,000 m of elevation gain. Mid-pack finishers take 35-45 hours; the overall cutoff is 46h30.
What does the UTMB predictor tell you?
The predictor uses the Riegel performance prediction model, adjusted for trail elevation using TrailMath's km-effort formula. Enter a race you have completed (any distance, any terrain) and the tool translates that performance to a UTMB equivalent, accounting for the 171km distance, 10,000m of gain and loss, and ultra fatigue scaling.
Understanding the output. The tool returns an optimistic and conservative estimate. For UTMB specifically, the conservative figure is more meaningful - UTMB's difficulty is heavily influenced by conditions (weather, heat, night navigation) that the model cannot capture. A runner with a 24-hour optimistic prediction should target 27-28 hours to account for UTMB's specific demands.
Reference race selection. For accurate UTMB prediction, use a reference race that is similar in character: ideally a mountain ultra of at least 50km with significant elevation. A flat road 100km will underpredict your UTMB time because the fatigue profile is different. The most reliable reference races are other UTMB World Series events (OCC, CCC, MCC) or comparable mountain ultras in the Alps.
Typical UTMB finish times by category: Elite (sub-24h), strong amateur (24-30h), mid-pack (30-38h), completion-focused (38-46h). The 30-hour mark roughly corresponds to a sub-3:00 road marathon equivalent in trail fitness.
Once you have a predicted finish time, use the UTMB Aid Station Planner to translate it into checkpoint splits and brief your crew.
Build a training plan targeted at your UTMB goal time
TrailMath uses these models to build periodized plans adjusted to your goals and terrain.
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