Naismith's rule at a glance
- Distance
- 1 hour per 3 miles
- About 20 minutes a mile on the flat
- Climb
- 1 hour per 2,000 ft
- Total elevation gain, not summit height
- Book time
- 30 min a mile + 30 min per 1,000 ft
- The AMC's slower version
- Not included
- Breaks
- Add about ten minutes in every hour
How do you use Naismith's rule?
Take the hike's distance in miles and divide it by three. Take its total elevation gain in feet and divide it by 2,000. Add the two, and the answer is the walking time in hours.
A 6-mile hike that climbs 2,000 feet comes out at two hours for the distance plus one hour for the climb: three hours. In metric the version usually quoted is an hour per 5 kilometers plus an hour per 600 meters of ascent, which is the same rule rounded.
Where did the rule come from?
William Naismith set it out in 1892, in a short note in the Scottish Mountaineering Club Journal about a spring day over three peaks. He covered ten miles and 6,300 feet of climbing in six and a half hours, short halts included, and the formula gives almost exactly that.
He was clear about who it described: men in fair condition on easy expeditions. That is a fit, experienced walker who stops only briefly, and it is why the rule reads fast for an ordinary day hiker.
What is book time, and how is it different?
Book time is the slower version used in the Appalachian Mountain Club's White Mountain Guide: 30 minutes a mile plus 30 minutes per 1,000 feet of climbing. It slows the flat pace from three miles an hour to two and keeps Naismith's climbing allowance, since 30 minutes per 1,000 feet is the same rate as an hour per 2,000. That lands closer to most day hikers. Treat both as walking time and add your breaks on top.
Where do both rules under-count?
Both treat downhill as free, and it isn't. A steep, rocky descent is slow because you pick every step, and Grand Canyon rangers tell hikers the climb back out takes about twice as long as the walk in.
They also cannot see the ground. Scrambles, rock steps, snow, mud and a heavy pack all slow you down, and so does a group, which moves at its slowest member's pace. A short, very steep trail such as Mount Tammany's Red Dot scores like any other mile and a bit, and climbs like something harder.
How long do real hikes take by Naismith's rule?
| Hike | Distance (mi) | Climb (ft) | Naismith's rule | Book time |
|---|---|---|---|---|
| Giant Ledge, Catskills | 3.2 | 1,100 | 1 h 35 min | 2 h 10 min |
| Mount Tammany Red Dot, up only | 1.2 | 1,201 | 1 h | 1 h 10 min |
| Cascade Mountain, Adirondacks | 4.8 | 1,940 | 2 h 35 min | 3 h 20 min |
| Slide Mountain, Catskills | 5.4 | 1,780 | 2 h 40 min | 3 h 35 min |
| Half Dome, Yosemite | 14 to 16 | 4,800 | 7 h to 7 h 45 min | 9 h 25 min to 10 h 25 min |
Distances and climbs from NY DEC, Lake Placid's tourism office, the National Park Service and Yosemite, as cited on our Basecamp pages. Walking time only, rounded to five minutes. Yosemite says most hikers take 10 to 12 hours for Half Dome.
What this means when you're choosing
- Total elevation gain for the route, not the summit's height above sea level
- Round-trip distance, since many trail pages list one way
- Which rule a guidebook time uses, so you know whether breaks are in it
- Your own pace from one timed hour on the trail, which beats any formula
Naismith's rule vs AMC book time
| Naismith's rule | AMC book time | |
|---|---|---|
| Flat pace | 3 miles an hour | 2 miles an hour |
| Climbing allowance | 1 hour per 2,000 ft | 30 minutes per 1,000 ft, the same rate |
| Written for | Fit walkers on easy expeditions, 1892 | Hikers on White Mountains trail |
| Breaks | Short halts only | Not included |
Which to pick: Use book time to plan an ordinary day hike, and Naismith's rule as the fast end of the range.
Work it out
How long will your hike take?
Enter the round-trip distance and the total climb. The defaults are Slide Mountain, the highest peak in the Catskills.
Naismith's rule
2 h 40 min
A fit walker taking short halts.
AMC book time
3 h 35 min
Closer to most day hikers.
Both are walking time. Add about ten minutes of rest for every hour, and more for a steep descent, rough ground or a group.
The common mistake
Planning the day on the formula alone
Naismith's rule is walking time for a fit hiker. Lunch, photos and every stop come on top, and the descent on tired legs is usually slower than the rule says. Use it to compare hikes, then add breaks and set a turnaround time before you leave the car.
Common questions
Is Naismith's rule accurate?
For a fit walker on good trail taking short halts, it is close. For most day hikers it runs fast, which is why the AMC's book time is slower. Neither counts real breaks, steep descents or rough ground.
How long does it take to hike a mile with 1,000 feet of elevation gain?
About 50 minutes by Naismith's rule and an hour by book time. A steep, rocky mile can take longer than either, and the walk back down is rarely as quick as the formulas assume.
Does Naismith's rule include breaks?
Only short halts. Book time includes none. Add about ten minutes of rest for every hour of walking, more for a group or with children.
Where this is defined
- Cruach Ardran, Stobinian, and Ben More (Scottish Mountaineering Club Journal, vol. 2 no. 3, September 1892), W. W. Naismith, via the University of Strathclyde's Glasgow Digital Library (Internet Archive copy)
- How to Know How Hard a Hike Will Be, Michael Lanza, The Big Outside
- Hiking Tips (Hike Smart), National Park Service, Grand Canyon National Park
- Half Dome Day Hike, National Park Service, Yosemite National Park