Leadville 100 · free tool

Leadville 100 Cutoff Calculator

Leadville is a 161 km out-and-back over 12,600 ft Hope Pass — twice. The 30-hour cutoff earns a silver buckle; sub-25 earns the big gold buckle. This calculator projects your ETA at every aid station, outbound and inbound.

160.9 km · Leadville, Colorado, USA
4,800 m elevation gain
30h00 total cutoff
Course loaded
Leadville Trail 100 Run
160.9 km · 11 enforced cutoffs · race cutoff 30:00:00

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

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

Why Leadville 100 is hard

What the GPX doesn't tell you.

  • Race start at 10,200 ft. Altitude is the dominant factor for anyone who hasn't lived above 8,000 ft for weeks.

  • Hope Pass at 12,600 ft, crossed twice. The double crossing breaks more runners than the distance does.

  • The "Boulevard" — 4 miles of dirt road back to the finish at 10,200 ft. Easy terrain that feels impossible after 95 miles.

Cutoff history

Leadville's cutoffs are tight in the first half (Mayqueen at 3h45m for 12.4 mi is aggressive) and relax through the middle, then tighten again on the inbound leg. The Twin Lakes inbound cutoff (10:15 PM = 18h15m) is the most-missed — runners arrive there with no quads left and 40 more miles to go.

The crux

Where the race is decided.

Twin Lakes outbound to Winfield turnaround — Hope Pass climb at altitude in the heat of midday. Pace too aggressively here and the inbound becomes a death march.

Pacing the cutoffs

Tactical advice for Leadville 100.

01

For sub-25 (gold buckle), target the Twin Lakes outbound cutoff with 90 minutes of buffer. The model accounts for terrain but not your altitude adaptation.

02

For sub-30 (silver buckle), getting to Winfield by 13 hours gives you 17 hours for the inbound — usually enough.

03

The Twin Lakes inbound aid (km 99) is the practical "do I finish" point. Cross it before 9:00 PM (15h elapsed) and you should make it.

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