Hiking Time Calculator (Naismith Rule)

1. Enter the total trail distance in kilometres.
2. Enter the total ascent, the height you will climb over the route.
3. Adjust your flat walking speed if you are faster or slower than 5 km/h.
4. Read the estimated moving time, split into walking and climbing time.

Naismith rule is a simple method for estimating how long a hike will take, devised by Scottish mountaineer William Naismith in 1892. It allows a steady walking pace across the distance, then adds extra time for the height climbed, because going uphill is much slower than walking on the flat.

The classic figures are one hour for every 5 kilometres and one hour for every 600 metres of ascent. It is the starting point almost every hill walker and mountain guide uses to plan a day on the hills.

1. Divide the distance by your flat walking speed for the walking time in hours.
2. Divide the total ascent in metres by 600 for the climbing time in hours.
3. Add the two together for the total moving time.
4. Add your own allowance for rests, food and photos on top.

The 600 metre figure means every 600 metres of climb adds roughly one hour, whatever the distance, which is why steep routes take far longer than their distance suggests.

You plan a 12 kilometre walk with 600 metres of ascent, at a steady 5 km/h. The walking time is 12 divided by 5, which is 2.4 hours, or 2 hours 24 minutes. The climbing time is 600 divided by 600, which is 1 hour. Together that is about 3 hours 24 minutes of moving time. Add half an hour of breaks and you should allow close to 4 hours for the day.

Ascent

Height gain is the biggest hidden cost; a short but steep route can take far longer than a long flat one.

Your Fitness and Pace

A fit walker may hold 5 to 6 km/h, while a heavy pack or a group slows the pace, so set the flat speed honestly.

Terrain and Ground

Bog, scree, snow and rough paths all slow you down beyond what distance and ascent alone predict.

Rests and Breaks

Naismith gives moving time only, so lunch, photos and navigation stops must be added separately.

The same distance takes very different times depending on the climb.

Notice the distance never changes, yet the ascent alone can more than double the time on the hill.

Planning a Route

Work out whether a day fits the daylight before you set off.

Setting a Turnaround

Combine the time estimate with your finish deadline to plan a safe turnaround point.

Telling Others Your Plan

Give a realistic finish time to whoever is expecting you back.

1. Ignoring Ascent

Judging a route by distance alone badly underestimates a steep day; always add the climb.

2. Forgetting Breaks

Naismith is moving time; a full day needs an allowance for rests on top.

3. Using an Optimistic Pace

Set a flat speed you can hold all day with your pack, not a short burst.

4. Skipping Terrain

Rough or boggy ground and snow slow you well below the estimate; add a margin in bad conditions.

Naismith rule is a reliable planning estimate for fit walkers on reasonable ground. It is a guide, not a guarantee, and does not model every condition.

Use Naismith rule: divide distance by your flat speed, then add the ascent in metres divided by 600. A 12 km walk with 600 m of climb is about 3 hours 24 minutes of moving time.

A hill-walking guide from 1892: allow one hour per 5 km on the flat, plus one hour for every 600 m of ascent, to estimate moving time.

No. It gives moving time only, so you must add your own allowance for rests, food, photos and navigation stops.

Roughly one hour for every 600 metres of ascent, regardless of distance, which is why steep routes take much longer than they look.

Naismith assumes about 5 km/h on the flat. Lower it to 4 or 4.5 km/h for a heavy pack, a group, or rough ground.

It is a good planning estimate for fit walkers on reasonable ground, but add a margin for bad terrain, snow, fatigue and breaks.

Gentle descent is covered by the walking pace, but very steep descent can be slow; some versions of the rule add time for that.

Add your rest allowance to the Naismith time, then check it fits within the daylight, leaving a safety buffer before dark.

No. The calculator runs entirely in your browser and nothing you enter is stored or sent anywhere.

• Naismith rule (Wikipedia).
• Hiking and hillwalking (Wikipedia).
• Grade and ascent (Wikipedia).