UTMB Cutoff Calculator
UTMB has only 4 enforced cutoffs across 174 km — but missing any of them ends your race. This calculator projects your arrival at each cutoff based on your fitness and the actual course profile.
What the GPX doesn't tell you.
174 km with ~9,900 m of vertical gain across the Alps — average grade is brutal even on the runnable sections.
Night running is unavoidable for most finishers — fatigue management compounds with altitude.
Cutoffs at Courmayeur (km 80, 21h) and Champex-Lac (km 124, 32h) are where most DNFs happen.
UTMB enforces only 4 cutoffs plus the finish (46h45). The Courmayeur cutoff at 21 hours catches runners who started too aggressively on the early climbs; the Champex-Lac cutoff at 32 hours catches those who blew up over the Grand Col Ferret. Champex is statistically the deadliest cutoff for finishers — many runners arrive there with no margin and DNF in the final third even though they technically made the cutoff.
Where the race is decided.
The stretch from Courmayeur (km 80) to Champex-Lac (km 124) — 44 km with two of the biggest climbs (Grand Col Ferret, Ferret) coming in the middle of the night. Pacing through this section is what separates finishers from DNFs.
Tactical advice for UTMB.
Pre-Courmayeur, target a pace that gets you there with at least 90 minutes of buffer. Tighter than that and the second half punishes you.
Champex-Lac is the practical "halfway test" — if you arrive with less than 60 minutes of buffer, you are unlikely to finish under cutoff.
Vallorcine (km 153) is technically the last cutoff but the climb to Tête aux Vents after Vallorcine is where late-race DNFs accumulate. Build buffer earlier.
More from RunPact.
- Ultra race time predictor — upload any GPX, get a course-aware finish time prediction.
- Custom cutoff calculator — for any race not in our featured list.
- Training plans — phase-based plans tailored to your race and current fitness.