About the Hiking Time Calculator
This hiking time calculator estimates how long a walk or hike will take once hills are taken into account. Enter the route distance, total elevation gain and total descent, and it gives two estimates: Naismith’s rule, the classic mountaineering rule of thumb used by guides and rescue teams, and Tobler’s hiking function, which models how walking speed changes with the steepness of the slope.
It is built for day hikers planning a turnaround time, backpackers splitting a route into days, and anyone checking whether they can finish before sunset. Adjust the pace factor for your fitness or pack weight, and add break time per hour for snacks, photos and navigation stops.
Both methods assume reasonable paths and average conditions. Rough terrain, snow, scrambling, heat or a large group can add a lot of time, so build in a margin and always carry a light.
With the default inputs, the estimated hiking time (naismith) is 3h 44m. Change any value above to recalculate instantly.
How to use the hiking time calculator
- 1Choose metric or imperial units.
- 2Enter the route distance and total elevation gain from your map or app.
- 3Enter the total descent (the same as the gain for a loop or out-and-back).
- 4Pick a pace that matches your group and pack, and add break minutes per hour.
- 5Compare the Naismith and Tobler estimates and plan with the longer one if in doubt.
Formula and method
Naismith’s rule (1892) allows one hour for every 5 km of horizontal distance plus one hour for every 600 m of ascent. It ignores descent, which suits gentle downhill paths but underestimates steep, rough ones.
Tobler’s hiking function gives walking speed from slope S (rise ÷ run): about 6 km/h on a slight downhill, 5 km/h on the flat and slowing sharply on steep climbs and descents. The calculator splits the route into an uphill and a downhill section in proportion to total climb and descent and assumes a steady slope on each. Both results are multiplied by your pace factor, and break minutes per hour of walking are added on top.
- D
- Horizontal distance in km
- A
- Total ascent in metres
- S
- Slope (vertical ÷ horizontal distance), negative downhill
- v
- Walking speed in km/h
Worked examples
12 km loop with 800 m of climbing
Naismith: 12 ÷ 5 = 2.4 h plus 800 ÷ 600 = 1.33 h, about 3 h 44 min. Tobler’s function, which rewards gentle slopes, estimates about 3 h 14 min.
8-mile trail with 2,000 ft up, leisurely pace and breaks
8 miles is 12.87 km and 2,000 ft is 609.6 m, so Naismith gives 2.57 + 1.02 = 3.59 h. The leisurely factor of 1.2 makes that 4.31 h, and 10 minutes of breaks per hour adds about 43 minutes for roughly 5 h 2 min in total.
Long mountain day: 20 km, 1,500 m up
Naismith gives 20 ÷ 5 + 1500 ÷ 600 = 4 + 2.5 = 6.5 hours of walking. Tobler estimates about 5 h 10 min, but on a big day fatigue usually pushes the real time toward the longer figure.
Frequently asked questions
What is Naismith’s rule?+
Naismith’s rule, devised by Scottish mountaineer William Naismith in 1892, allows 1 hour for every 5 km (3 miles) walked plus 1 hour for every 600 m (2,000 ft) of ascent. It is still the standard planning rule in UK hill walking.
How long does it take to hike 10 miles?+
On flat ground at an average 3 mph pace, about 3 hours 20 minutes of walking. Add roughly an hour for every 2,000 ft of climbing plus your breaks — a hilly 10-mile hike often takes 5–6 hours in total.
Why is Tobler faster than Naismith for some hikes?+
Tobler’s function allows about 6 km/h on gentle downhills and 5 km/h on the flat, so routes with long easy descents come out quicker. Naismith ignores descent entirely but adds a flat hour per 600 m of climbing.
How much extra time should I allow for descents?+
Langmuir’s correction to Naismith subtracts 10 minutes per 300 m of gentle descent (5–12°) and adds 10 minutes per 300 m of steep descent (over 12°). Steep, loose or rocky downhills can be as slow as climbing.
How do I account for a heavy backpack?+
Choose the heavy-pack pace factor (×1.4), which adds 40% to walking time. Multi-day backpackers carrying 15 kg or more are commonly 30–50% slower than day hikers on the same trail.