Race Time Predictor
How fast will you run Demi tOur du Lac?
Demi tOur du Lac race stats pre-loaded (56.49 km, 3,481 m D+). Enter a known race result to get an elevation-adjusted finish time estimate.
56.49km3,481m D+Winner: ~5h17Cutoff: 11h28
Full MaXi-Race Demi tOur du Lac course data: aid stations, cutoffs, course profile
- ✓Your race (done)
- 2About you
- 3Your finish
1Your race
- The course
56.5 km, but it costs 109 km-effort. The 3,491 m of descent is where legs go.
2How should we estimate you?
Start with
Pick whichever you have. After your first estimate we ask for the other - two inputs give a firmer read.
Same as gain. Edit if different.
Hours, or h:mm
- TrailMath
Got a UTMB index? Hand it over, it's the straightest read I get. No index? A long, hilly past race works too.
3 · Your predicted finish
91 km-effort (ITRA, gain only)109 km-effort
Add a past race or your index to get a finish time.
Demi tOur du Lac finish times by UTMB Index
Predicted finish on the Demi tOur du Lac course (56.5 km, 3,481 m D+) for each UTMB Index, with the margin to the 11h28 cutoff.
| UTMB Index | Predicted finish | Average pace | Margin to cutoff |
|---|---|---|---|
| 850 | 5h49 | 6:11 /km9:57 /mi | +5h39 |
| 800 | 6h22 | 6:46 /km10:53 /mi | +5h06 |
| 750 | 6h57 | 7:23 /km11:54 /mi | +4h31 |
| 700competitive | 7h36 | 8:05 /km13:00 /mi | +3h52 |
| 650 | 8h19 | 8:50 /km14:13 /mi | +3h09 |
| 600 | 9h05 | 9:39 /km15:32 /mi | +2h23 |
| 550 | 9h56 | 10:33 /km16:59 /mi | +1h32 |
| 500mid-pack | 10h51 | 11:32 /km18:34 /mi | +0h37 |
| 450 | 11h52 | 12:36 /km20:17 /mi | 0h24 past the cutoff |
| 400back of the pack | 12h58 | 13:47 /km22:11 /mi | 1h30 past the cutoff |
| 350 | 14h11 | 15:04 /km24:14 /mi | 2h43 past the cutoff |
| 300 | 15h30 | 16:28 /km26:30 /mi | 4h02 past the cutoff |
The 11h28 cutoff sits at about Index 469. The typical winning time, 5h17, sits at about Index 905. At the 2026 edition, the median of the 1,244 finishers took 9h30, about Index 575. A model estimate, not an official ITRA or UTMB figure.
From a result you already have
What the predictor gives on Demi tOur du Lac for a few common reference results.
| Road marathon | 3h00 → 9h34 | 3h30 → 11h10 | 4h00 → 12h45 | 4h30 → 14h21 |
|---|---|---|---|---|
| 50 km trail, 2,000 m D+ | 5h30 → 8h00 | 6h30 → 9h28 | 7h30 → 10h55 | 8h30 → 12h22 |
Road marathons use the tool's rougher power-law fallback.
Demi tOur du Lac course in numbers
- Climbing per kmClimbing per mile
- 62 m325 ft
- ITRA km-effort
- 91 (50K)
- Highest point
- 1,645 m5,397 ft
- Biggest climb
- +698 m over 4.7 km at 14.4%+2,290 ft over 2.9 mi at 14.4%
- Steepest climb
- +683 m over 2.8 km at 24.0%+2,241 ft over 1.7 mi at 24.0%
- Longest descent
- -912 m over 7.6 km at 11.8%-2,992 ft over 4.7 mi at 11.8%
- Track climbing above 3%
- 38%
- Winning time / cutoff
- 5h17 / 11h28 (2.2x the winner's time)
Section-by-section climbs, descents and grades are on the Demi tOur du Lac course page.
Predict your Demi tOur du Lac finish time from a reference race result, adjusted for the course's 56.49 km and roughly 3,481 m of elevation gain. The overall cutoff is 11h28.
About MaXi-Race Demi tOur du Lac
MaXi-Race Demi tOur du Lac covers 56.49 km with around 3,481 m of elevation gain, starting in Doussard, France. The overall cutoff is 11 hours 28 minutes.
Crew access is allowed at Base vie Semnoz (in) (36.1 km) and Base vie Semnoz (out) (36.4 km). Drop bags are available at Base vie Semnoz (in) and Base vie Semnoz (out).
Checkpoint data approximate - verify against the current official race guide at maxi-race.org before your race.
How the prediction works
Your result becomes a UTMB Index, mapped onto Demi tOur du Lac by the calibrated model behind the ITRA / UTMB Index Estimator. Full methodology.
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