What is a "vert per mile" number?

Vert per mile is the average elevation gain divided by total distance. Western States 100 averages 180 ft/mi. Hardrock 100 averages 330 ft/mi. UTMB averages 295 ft/mi. Anything over 200 ft/mi is a "climby" course.

Does descent slow you down too?

It can — quad fatigue late in a 100-miler often costs as much time as the climbs. Most rule-of-thumb calculations only adjust for ascent because descent timing varies wildly with technique and trail conditions.

Vert Calculator · Endure Weekly

Q: How much time does vert add to a race?

Naismith's Rule estimates ten minutes added per 1,000 feet of elevation gain. For most ultrarunners with weak climbers' legs, the real penalty is closer to twelve to fifteen minutes per 1,000 feet on race day.

What this calculator actually does

Most ultrarunners under-budget for the climb. You train at sea level, you've got a flat-pace target in your head from the marathon you ran in October, and then you arrive at a course with 18,000 feet of vert and your finish time blows up by three hours. This calculator does the math you should have done in March.

The base calculation is Naismith's Rule, a Scottish hill-walker's heuristic from 1892: add ten minutes per 1,000 feet of climb to a flat-pace estimate. It still works, mostly, for most people. We add an Aitken correction as the default — twelve minutes per 1,000 feet — because most ultrarunners aren't Scottish hill-walkers and we lose more time on technical climbs than the strict rule predicts.

Vert per mile, by race

The "vert per mile" number is the single best way to judge how climby a course is. For reference:

Race	Distance	Vert (ft)	Vert/mile
Boston Marathon	26.2 mi	820	31
Western States 100	100 mi	18,000	180
UTMB (CCC)	62 mi	19,000	306
Leadville Trail 100	100 mi	15,600	156
UTMB	106 mi	31,500	297
Hardrock 100	100 mi	33,000	330
Cocodona 250	250 mi	40,000	160
Tor des Géants	205 mi	79,000	385

Anything over 200 ft/mi is climby. Over 300 ft/mi is mountain ultra territory. Hardrock and Tor are in a category of their own — at that vert/mile, you're hiking 30–40% of the course no matter how fit you are.

How to use the climbing-cost rate dropdown

The default 12 min/1,000 ft (Aitken) is the right starting point for most well-trained ultrarunners on a course they haven't seen. Adjust based on:

Strict Naismith (10 min/1,000 ft) — strong on hills, course you know, daylight climbing only.
Strong climber (8 min/1,000 ft) — you've been doing 1,500 ft/week vert specifically, you race well in mountains.
Aitken (12 min/1,000 ft) — the safe default. Most ultrarunners.
Weak climber, late race (15 min/1,000 ft) — for the last quarter of a 100, when quads are gone and you're walking everything over 6%.

The honest caveats

A vert calculator gives you a finish-time estimate, not a finish-time. It assumes you fueled correctly, didn't twist an ankle, didn't get lost, didn't have to wait at a creek crossing, and didn't sit at an aid station for forty minutes feeling sorry for yourself. None of those are guaranteed. Ultras are decided by the things the calculator can't know.

Use this as a sanity check, not a goal. If your goal time and the calculator's estimate disagree by more than 10%, one of them is wrong — and it's usually not the calculator.

Frequently asked

How much time does vert add to a race?

Naismith's Rule says 10 minutes per 1,000 feet of gain. Most ultrarunners experience 12–15 min/1,000 ft on race day, especially in the back half. A 20,000-foot course adds roughly 4 hours to a flat estimate.

Should I use feet or meters?

Whichever your race lists. North American races publish vert in feet; European mountain ultras publish it in meters. Don't mix them — 1,000 m of climb is more than 3,000 ft, and the time penalty changes accordingly.

Why doesn't this account for descent?

Because descent timing varies too much. A trained mountain runner might gain 30 seconds per 1,000 ft of descent. A flatlander with quads on fire late in a 100 will lose 90 seconds. We'd rather give you a clean climb-only estimate than pretend we know your downhill technique.