Hiking Time Calculator (Naismith’s Rule)
Estimate how long a hike will take from its distance and total ascent using Naismith’s rule, the classic mountain time formula.
How it works
Naismith’s rule: time = distance ÷ flat-pace + ascent ÷ 600 m per hour · (allow 1 hour per 5 km plus 1 hour per 600 m of climb)
Naismith’s rule, devised by a Scottish mountaineer in 1892, gives a quick walking-time estimate: allow one hour for every 5 km of distance, and add an extra hour for every 600 metres of ascent. It assumes reasonable fitness and easy terrain, and it deliberately ignores descent, rests and rough ground. It is a planning baseline — add margin for heavy packs, difficult footing or fatigue.
Worked example
A 12 km route with 800 m of ascent needs 12 ÷ 5 = 2.4 hours for the distance plus 800 ÷ 600 = 1.33 hours for the climb, totalling about 3 hours 44 minutes before any breaks.
Sources: Naismith’s rule — Wikipedia
Frequently asked questions
Does Naismith’s rule account for going downhill?
Not in its basic form — it assumes gentle descents take no extra time. Refinements like Tranter’s corrections and Scarf’s equation adjust for steep descents and fitness; for most hikes the base rule plus a rest allowance is close enough.
Should I add time for breaks?
Yes. Naismith’s rule is pure moving time. Add your expected rest, lunch and photo stops on top, and pad further for bad weather, navigation or a tired group.
Why 600 metres per hour for climbing?
That was Naismith’s original allowance — one extra hour per 2,000 feet (about 600 m) of ascent. It reflects how much steep uphill slows a walker compared with covering flat ground.
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