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Western States 100 cutoff calculator

Western States enforces cutoffs at every aid station across 161 km. The cumulative effect of staying ahead of each one is what separates a sub-30-hour buckle from a DNF. This calculator projects your ETA at every checkpoint.

161.3 km · Olympic Valley to Auburn, California, USA
5,500 m elevation gain
30h00 total cutoff

This calculator spreads your target time evenly. To see when real finishers actually reached each aid station, open Western States 100 by the numbers.

Course loaded
Western States Endurance Run
161.3 km · 20 cutoffs before the finish · race cutoff 30:00:00

Defaults to the race cutoff. Set a faster goal to see your buffer at every aid station.

Want a course-aware ETA instead? Try the predictor →

ETAs use a linear pace projection from your target finish time. That is useful for cutoff planning but does not account for where the elevation gain sits on the course.

Why Western States 100 is hard

What the GPX doesn't tell you

  • Heat. The American River canyons routinely hit 35°C or more. That is not in the GPX, but it will slow you down 10 to 20% in the heat of the day.

  • Asymmetric profile: 5,500 m of climb, 7,000 m of descent. Quad damage from runnable descents is the late-race killer.

  • 20 aid stations before the finish, each with an enforced cutoff. Miss any one of them and you are pulled from the race.

Cutoff history

WSER cutoffs are generous in the first half but tighten significantly past Foresthill (km 100). The most-missed cutoffs historically are at Devil's Thumb (km 77), Michigan Bluff (km 90), and Foresthill itself, all in the heat of the day. Each cutoff is the deadline for leaving the aid station, not for arriving.

The crux

The sections that decide the race

Last Chance (km 70) to Foresthill (km 100). The canyons section combines the steepest climbs, highest temperatures, and the cumulative fatigue of the first marathon-and-a-half. Most non-finishers DNF here.

Pacing the cutoffs

Advice for Western States 100

01

Aim to leave Robinson Flat (km 49) with at least 2 hours of buffer, because the canyons will eat that margin.

02

Foresthill (km 100) is the practical “do I finish” checkpoint. With 2+ hours of buffer here, you have a real shot at 30 hours.

03

After Rucky Chucky (km 125), the climbing eases but quad damage from earlier descents starts dictating pace. Build buffer before the river crossing, not after.

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