User Rating 0.0
Total Usage 0 times
km/h
Avg hiker: 4-5 km/h
Moving Time:--
Breaks (10m/hr):--
Total Duration:--

Pace Analysis: -- min/km

Vertical Penalty: +-- mins

Is this tool helpful?

Your feedback helps us improve.

About

Accurate trip planning is essential for safety in backcountry environments. Underestimating the time required to traverse a route can lead to unplanned night hiking, exhaustion, or exposure to adverse weather conditions. This calculator employs Naismith's Rule, a heuristic developed by Scottish mountaineer William Naismith in 1892, with modern Langmuir corrections to account for fitness and terrain.

The standard Naismith rule assumes a base speed of 5 km/h on flat terrain, adding 1 hour for every 600 m of ascent. However, real-world hiking involves variables such as pack weight (the "burden") and surface resistance (sand, snow, scree). This tool integrates these factors to provide a conservative estimate for moving time and total trip duration.

hiking trekking naismith walking outdoors

Formulas

The calculation uses the modified Naismith-Langmuir formula:

T dvft + h600 + tb

Where T is total time, d is distance (km), v is base speed (km/h), ft is the terrain factor (dimensionless, usually 1.0), h is elevation gain (m), and tb represents break times calculated per interval.

Reference Data

Terrain TypeCorrection Factor (ft)Impact Description
Paved / Road1.0Ideal conditions. No speed loss.
Groomed Trail1.0Standard hiking path.
Rough Trail0.8Roots, rocks, uneven steps.
Off-Trail / Bushwhack0.6Dense vegetation or navigation required.
Sand / Loose Gravel0.5High energy expenditure, significant slippage.
Snow (Post-holing)0.3 - 0.5Extremely slow without flotation gear.
Steep Scramble0.4Requires hands; verticality slows horizontal progress.
Heavy Pack (>15kg)10%Additional penalty applied to base speed.

Frequently Asked Questions

Naismith's Rule does not account for descent difficulty. While walking downhill is generally faster, steep descents (grades > 20 degrees) or loose terrain can significantly reduce speed due to braking forces required to maintain stability.
Heavy loads increase metabolic cost. A general rule of thumb is a 5-10% speed reduction for packs exceeding 15% of body weight, though this tool uses a configurable penalty based on the input weight.
No. Trail running biomechanics differ significantly. Naismith's Rule is calibrated for a walking gait. Runners should use Tobler's Hiking Function or specific running pace calculators.
Standard hiking protocol suggests a 10-minute break every hour. This prevents lactic acid buildup and allows for hydration/calorie replenishment without cooling muscles down too much.