Skip to content
TrailMath
Language EN FR
90km du Mont-Blanc

90km du Mont-Blanc Aid Station Planner

All 18 90km du Mont-Blanc checkpoints pre-loaded. Enter your goal finish time to get estimated arrival times at every aid station.

88.8km6,137m D+18 checkpointsCutoff: 24h20

Full 90km du Mont-Blanc course data: aid stations, cutoffs, course profile

Enter a goal 90km du Mont-Blanc finish time and get estimated arrival times at every checkpoint - 88.8 km with around 6,137 m of climbing, with crew and drop-bag points flagged.

Turns every arrival into a clock time and every cutoff into a margin.

Terrain changes how the goal time is shared between segments, not the total. One surface everywhere cancels out.

Checkpoints (18)

Cutoff Fri 09:35

Cutoff Fri 11:35

Cutoff Fri 13:05

Cutoff Fri 15:05

Cutoff Fri 16:05

Cutoff Fri 20:20

Cutoff Fri 22:20

Cutoff Sat 00:50

Cutoff Sat 02:50

Cutoff Sat 05:05

Crew may meet you at
  • Planpraz 12.7 km, by Fri 08:00
  • Le Buet 28.5 km, by Fri 10:44
  • Emosson 40.6 km, by Fri 13:30
  • Les Esserts 48.4 km, by Fri 15:22
  • Le Tour 60.1 km, by Fri 17:52
  • Les Bois 69.7 km, by Fri 19:22
  • Montenvers 75.2 km, by Fri 20:47
Drop bags

The organiser publishes no drop-bag service anywhere on this course.

  1. Breventlikely hiking (pace)

    Fri 07:27

    Leave by Fri 08:11Set by La Flegere

    Dist (km)
    10.2
    D+ (m)
    +1556
    Seg time
    2:42:52
    Seg pace/km
    15:58

  2. Planprazlikely hiking (pace)

    Fri 08:00

    Leave by Fri 08:44Set by La Flegere

    Dist (km)
    12.7
    D+ (m)
    +45
    Seg time
    0:33:04
    Seg pace/km
    13:14

  3. La Flegere

    Fri 08:51

    Cutoff Fri 09:3544 minTight

    Leave by Fri 09:41Set by Le Buet

    Dist (km)
    18.0
    D+ (m)
    +140
    Seg time
    0:50:09
    Seg pace/km
    9:28

  4. Tete aux Ventslikely hiking (pace)

    Fri 09:35

    Leave by Fri 10:26Set by Le Buet

    Dist (km)
    21.7
    D+ (m)
    +313
    Seg time
    0:44:39
    Seg pace/km
    12:04

  5. Le Buet

    Fri 10:44

    Cutoff Fri 11:3551 minTight

    Leave by Fri 11:42Set by La Villaz

    Dist (km)
    28.5
    D+ (m)
    +25
    Seg time
    1:08:22
    Seg pace/km
    10:03

  6. La Villazlikely hiking (pace)

    Fri 12:06

    Cutoff Fri 13:0558 minTight

    Leave by Fri 13:40Set by Emosson

    Dist (km)
    35.1
    D+ (m)
    +447
    Seg time
    1:22:40
    Seg pace/km
    12:32

  7. Emossonlikely hiking (pace)

    Fri 13:30

    Cutoff Fri 15:051h34

    Leave by Fri 15:10Set by Le Chatelard

    Dist (km)
    40.6
    D+ (m)
    +756
    Seg time
    1:24:09
    Seg pace/km
    15:18

  8. Le Chatelardlikely hiking (pace)

    Fri 14:24

    Cutoff Fri 16:051h40

    Leave by Fri 16:51Set by Le Tour

    Dist (km)
    44.7
    D+ (m)
    +37
    Seg time
    0:54:03
    Seg pace/km
    13:11

  9. Les Essertslikely hiking (pace)

    Fri 15:22

    Leave by Fri 17:49Set by Le Tour

    Dist (km)
    48.4
    D+ (m)
    +538
    Seg time
    0:57:32
    Seg pace/km
    15:33

  10. Alpage de Catognelikely hiking (pace)

    Fri 16:00

    Leave by Fri 18:27Set by Le Tour

    Dist (km)
    51.0
    D+ (m)
    +357
    Seg time
    0:38:06
    Seg pace/km
    14:39

  11. Col des Posetteslikely hiking (pace)

    Fri 16:58

    Leave by Fri 19:25Set by Le Tour

    Dist (km)
    55.1
    D+ (m)
    +348
    Seg time
    0:57:45
    Seg pace/km
    14:05

  12. Le Tour

    Fri 17:52

    Cutoff Fri 20:202h27

    Leave by Fri 20:50Set by Les Bois

    Dist (km)
    60.1
    D+ (m)
    +83
    Seg time
    0:54:38
    Seg pace/km
    10:56

  13. Les Bois

    Fri 19:22

    Cutoff Fri 22:202h58

    Leave by Fri 23:25Set by Montenvers

    Dist (km)
    69.7
    D+ (m)
    +190
    Seg time
    1:29:07
    Seg pace/km
    9:17

  14. Montenverslikely hiking (pace)

    Fri 20:47

    Cutoff Sat 00:504h03

    Leave by Sat 01:38Set by Plan de l'Aiguille

    Dist (km)
    75.2
    D+ (m)
    +825
    Seg time
    1:24:55
    Seg pace/km
    15:26

  15. Le Signallikely hiking (pace)

    Fri 21:17

    Leave by Sat 02:09Set by Plan de l'Aiguille

    Dist (km)
    77.0
    D+ (m)
    +306
    Seg time
    0:30:40
    Seg pace/km
    17:02

  16. Plan de l'Aiguille

    Fri 21:58

    Cutoff Sat 02:504h51

    Leave by Sat 03:41Set by Chamonix (Finish)

    Dist (km)
    81.2
    D+ (m)
    +161
    Seg time
    0:40:49
    Seg pace/km
    9:43

  17. Chamonix (Finish)

    Fri 23:22

    Cutoff Sat 05:055h43

    Dist (km)
    88.8
    D+ (m)
    +10
    Seg time
    1:23:28
    Seg pace/km
    10:59

Highlighted rows use a pace heuristic (>12 min/km / >19 min/mi) - likely hiking by speed, not grade. The grade-based power-hike cue is ≥15% (see GAP and Incline tools). Times are distributed proportionally by km-effort.

Leave by is the latest you can start the next segment and still make every cutoff ahead of you at this pace - often set by a station further on, not this one. It does not yet subtract the time you spend stopped, so treat it as the optimistic edge.

Cutoff buffers are estimates from your goal time and published barriers. Courses and barriers change - verify against the official race guide.

Next step

Calculate nutrition →

About 90km du Mont-Blanc

90km du Mont-Blanc covers 88.8 km with around 6,137 m of elevation gain, starting in Chamonix, France. The overall cutoff is 24 hours 20 minutes.

Crew access is allowed at Planpraz (12.7 km), Le Buet (28.5 km), Emosson (40.6 km), Les Esserts (48.4 km), Le Tour (60.1 km), Les Bois (69.7 km) and Montenvers (75.2 km).

Checkpoint data approximate - verify against the current official race guide at marathonmontblanc.fr before your race.

The science behind km-effort pacing

Most runners build race pacing plans by dividing total distance evenly - which ignores the fact that an uphill kilometre takes far longer than a flat one. This planner uses TrailMath's enhanced km-effort model to distribute your goal time proportionally by effort, not by distance.

The km-effort formula for each segment is: distance_km + gain_m/100 + loss_m/200. This is TrailMath's extension of the standard ITRA gain-only formula (model TM1, where the descent divisor is a published convention), which adds descent cost because steep technical descents carry real eccentric load. A 5km segment with 500m of gain and 200m of loss has an effort of 5 + 5 + 1 = 11 effort-km - equivalent to running 11km flat. Time is allocated proportionally to this effort score.

Why gain and loss have asymmetric costs. Minetti et al. (2002) mapped the metabolic cost of inclined locomotion across gradients from -45% to +45%. The key findings: metabolic cost rises steeply above 15-20% uphill grade, making power hiking more energy-efficient than running on steep climbs. On descents, eccentric muscle loading (quads acting as brakes) creates its own metabolic cost - steep technical descents are far more demanding than the same gradient on a smooth fire road. The gain/100 + loss/200 asymmetry in the formula reflects this - gain is more costly per metre than loss, but loss is not free.

Power hiking threshold is flagged at segments where your computed pace exceeds 12 min/km (19 min/mile). This threshold corresponds to the crossover point where walking biomechanics become more efficient than running on steep uphill terrain. Strategic power hiking on marked segments preserves leg muscle for descents and reduces overall race time compared to running everything.

This km-effort model is the same formula used in TrailMath's training engine for load calculation (following Dan Johnston's asymmetric elevation scoring methodology), ensuring consistency between how your training load is measured and how your race effort is planned.

Minetti AE et al. (2002). Energy cost of walking and running at extreme uphill and downhill slopes. J Appl Physiol. 93(3):1039-46. Minetti AE et al. (1995). Mechanical determinants of gradient walking energetics in man. J Physiol. 481(Pt 1):235-43. ITRA. km-effort formula. International Trail Running Association. itra.run

Related tools

90km du Mont-Blanc Finish Time Predictor Predict your 90km du Mont-Blanc finish time Nutrition Calculator Calories, carbs & hydration targets Aid Station Planner Checkpoint times & pacing plan

Track your 90km du Mont-Blanc plan, crew notes, and live progress in the app

TrailMath uses these models to build periodized plans adjusted to your goals and terrain.

Start free