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UTMB Mont-Blanc

UTMB Aid Station Planner

All 18 UTMB checkpoints pre-loaded. Enter your goal finish time to get estimated arrival times at every aid station from Chamonix to Chamonix.

174km10,000m D+23 checkpointsCutoff: 45h45

Full UTMB Mont-Blanc course data: aid stations, cutoffs, course profile

Enter a goal UTMB finish time and get estimated arrival times at all major checkpoints from Chamonix through Courmayeur and Champex-Lac back to Chamonix - 174 km and around 10,000 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 (24)

Cutoff Sat 00:00

Cutoff Sat 02:00

Cutoff Sat 04:00

Cutoff Sat 07:15

Cutoff Sat 11:00

Cutoff Sat 14:15

Cutoff Sat 19:15

Cutoff Sat 23:45

Cutoff Sun 03:30

Cutoff Sun 09:00

Cutoff Sun 12:15

Cutoff Sun 15:45

Cutoff Sun 17:30

Crew may meet you at
  • Les Contamines 32.4 km, by Sat 02:12
  • Courmayeur 81.3 km, by Sat 13:08
  • Champex-Lac 127.5 km, by Sat 23:01
  • Vallorcine 155.3 km, by Sun 05:20
Drop bags
  • Courmayeur 81.3 km, by Sat 13:08
  • Champex-Lac 127.5 km, by Sat 23:01

  1. Col de Vozalikely hiking (pace)

    Fri 22:40

    Leave by Fri 22:15Set by Saint-Gervais

    Dist (km)
    14.5
    D+ (m)
    +898
    Seg time
    2:55:30
    Seg pace/km
    12:06

  2. Saint-Gervaislikely hiking (pace)

    Sat 00:25

    Cutoff Sat 00:00-25 minBehind cutoff

    Leave by Sat 00:12Set by Les Contamines

    Dist (km)
    22.9
    D+ (m)
    +142
    Seg time
    1:44:36
    Seg pace/km
    12:27

  3. Les Contamines

    Sat 02:12

    Cutoff Sat 02:00-13 minBehind cutoff

    Leave by Sat 02:15Set by La Balme

    Dist (km)
    32.4
    D+ (m)
    +495
    Seg time
    1:47:41
    Seg pace/km
    11:20

  4. La Balmelikely hiking (pace)

    Sat 03:57

    Cutoff Sat 04:002 minTight

    Leave by Sat 04:26Set by Les Chapieux

    Dist (km)
    41.1
    D+ (m)
    +595
    Seg time
    1:44:49
    Seg pace/km
    12:03

  5. Refuge de la Croix du Bonhommelikely hiking (pace)

    Sat 05:36

    Leave by Sat 06:05Set by Les Chapieux

    Dist (km)
    46.9
    D+ (m)
    +794
    Seg time
    1:38:57
    Seg pace/km
    17:04

  6. Les Chapieuxlikely hiking (pace)

    Sat 06:45

    Cutoff Sat 07:1529 minTight

    Leave by Sat 07:32Set by Lac Combal

    Dist (km)
    52.2
    D+ (m)
    +0
    Seg time
    1:09:20
    Seg pace/km
    13:05

  7. Col de la Seignelikely hiking (pace)

    Sat 09:19

    Leave by Sat 10:06Set by Lac Combal

    Dist (km)
    62.9
    D+ (m)
    +1053
    Seg time
    2:33:10
    Seg pace/km
    14:19

  8. Lac Combal

    Sat 10:12

    Cutoff Sat 11:0047 minTight

    Leave by Sat 11:19Set by Courmayeur

    Dist (km)
    67.8
    D+ (m)
    +0
    Seg time
    0:53:56
    Seg pace/km
    11:00

  9. Arete du Mont-Favrelikely hiking (pace)

    Sat 11:14

    Leave by Sat 12:21Set by Courmayeur

    Dist (km)
    71.8
    D+ (m)
    +464
    Seg time
    1:01:44
    Seg pace/km
    15:26

  10. Checrouit - Maison Vieille

    Sat 12:04

    Leave by Sat 13:11Set by Courmayeur

    Dist (km)
    76.4
    D+ (m)
    +14
    Seg time
    0:49:52
    Seg pace/km
    10:50

  11. Courmayeurlikely hiking (pace)

    Sat 13:08

    Cutoff Sat 14:151h07Tight

    Leave by Sat 15:15Set by Arnouvaz

    Dist (km)
    81.3
    D+ (m)
    +20
    Seg time
    1:03:52
    Seg pace/km
    13:02

  12. Refuge Bertonelikely hiking (pace)

    Sat 14:44

    Leave by Sat 16:50Set by Arnouvaz

    Dist (km)
    86.6
    D+ (m)
    +813
    Seg time
    1:35:55
    Seg pace/km
    18:06

  13. Refuge Bonatti

    Sat 16:09

    Leave by Sat 18:16Set by Arnouvaz

    Dist (km)
    94.2
    D+ (m)
    +312
    Seg time
    1:25:10
    Seg pace/km
    11:12

  14. Arnouvaz

    Sat 17:08

    Cutoff Sat 19:152h07Tight

    Leave by Sat 20:25Set by La Fouly

    Dist (km)
    99.4
    D+ (m)
    +127
    Seg time
    0:58:55
    Seg pace/km
    11:20

  15. Grand Col Ferretlikely hiking (pace)

    Sat 18:35

    Leave by Sat 21:52Set by La Fouly

    Dist (km)
    104.0
    D+ (m)
    +760
    Seg time
    1:26:39
    Seg pace/km
    18:50

  16. La Fouly

    Sat 20:27

    Cutoff Sat 23:453h17

    Leave by Sun 00:55Set by Champex-Lac

    Dist (km)
    114.0
    D+ (m)
    +87
    Seg time
    1:52:31
    Seg pace/km
    11:15

  17. Champex-Lac

    Sat 23:01

    Cutoff Sun 03:304h28

    Leave by Sun 05:26Set by Trient

    Dist (km)
    127.5
    D+ (m)
    +512
    Seg time
    2:34:22
    Seg pace/km
    11:26

  18. La Gietelikely hiking (pace)

    Sun 01:32

    Leave by Sun 07:56Set by Trient

    Dist (km)
    138.9
    D+ (m)
    +794
    Seg time
    2:30:09
    Seg pace/km
    13:10

  19. Trientlikely hiking (pace)

    Sun 02:35

    Cutoff Sun 09:006h25

    Leave by Sun 09:29Set by Vallorcine

    Dist (km)
    144.0
    D+ (m)
    +63
    Seg time
    1:03:18
    Seg pace/km
    12:25

  20. Les Tseppeslikely hiking (pace)

    Sun 03:49

    Leave by Sun 10:44Set by Vallorcine

    Dist (km)
    148.0
    D+ (m)
    +647
    Seg time
    1:14:30
    Seg pace/km
    18:37

  21. Vallorcinelikely hiking (pace)

    Sun 05:20

    Cutoff Sun 12:156h54

    Leave by Sun 12:55Set by Chamonix (Finish)

    Dist (km)
    155.3
    D+ (m)
    +144
    Seg time
    1:30:45
    Seg pace/km
    12:26

  22. La Flegerelikely hiking (pace)

    Sun 07:59

    Cutoff Sun 15:457h45

    Leave by Sun 15:34Set by Chamonix (Finish)

    Dist (km)
    166.6
    D+ (m)
    +953
    Seg time
    2:38:53
    Seg pace/km
    14:04

  23. Chamonix (Finish)likely hiking (pace)

    Sun 09:55

    Cutoff Sun 17:307h35

    Dist (km)
    174.0
    D+ (m)
    +313
    Seg time
    1:55:27
    Seg pace/km
    15:36

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 →

UTMB Mont-Blanc course in numbers

Climbing per km
57 m
ITRA km-effort
274 (100M)
Highest point
2,537 m
Biggest climb
+1,909 m over 23.4 km at 7.2% (Saint-Gervais to Refuge de la Croix du Bonhomme)
Steepest climb
+762 m over 4.2 km at 17.9% (through Grand Col Ferret)
Longest descent
-1,270 m over 14.1 km at 8.3% (through La Fouly)
Track climbing above 3%
40%
Winning time / cutoff
20h00 / 45h45 (2.3x the winner's time)

Section-by-section climbs, descents and grades are on the UTMB Mont-Blanc course page.

About UTMB Mont-Blanc

The Ultra-Trail du Mont-Blanc is a 174km loop circumnavigating the Mont-Blanc massif through France, Italy, and Switzerland, with 10,000m of elevation gain and loss. Starting and finishing in Chamonix, it is one of the most competitive and sought-after ultra-trail races in the world.

Key sections and where the race is won and lost. The opening 50km to Les Chapieux are deceptively demanding - three significant cols (Col du Voza, Col du Bonhomme, Col de la Croix du Bonhomme) set the tone. Most DNFs happen in the 46km section between Courmayeur (81.3km) and Champex-Lac (127.5km), which has no crew access anywhere in between. The final climb from Vallorcine (155.3km) to La Flegere at 1200m of gain after 150km of racing is where the race truly ends for many runners.

Crew access points: Les Contamines (32.4km), Courmayeur (81.3km), Champex-Lac (127.5km), Vallorcine (155.3km). Drop bags allowed at Courmayeur and Champex-Lac only.

Pacing guidance. The planner uses TrailMath's km-effort model to distribute your goal time across segments proportionally to their effort cost. For a 30-hour finish, expect roughly: Saint-Gervais 3:30, Courmayeur 13:00, Champex-Lac 21:00, Vallorcine 26:30. These are effort-proportional estimates - adjust for the night penalty (TrailMath plans for roughly 15-20% between 21:00 and 05:00, weighted toward the 02:00-04:00 low) and your individual strengths on climbs vs descents.

Checkpoint data approximate - verify against current official UTMB race guide at utmb.world before your race.

How the splits are allocated

Your goal time is split across the UTMB Mont-Blanc legs by km-effort: distance + gain/100 + loss/200. Full methodology.

Related tools

Race Time Predictor Predict your UTMB finish time Nutrition Calculator Calories, carbs & hydration targets Aid Station Planner Plan any race checkpoint by checkpoint

Track your UTMB plan, crew notes, and live progress in the app

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

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