Hike Duration Estimator (Naismith's rule)
Time = horizontal distance ÷ 5 km/h + 1 hr per 600 m ascent. With Tranter's fitness corrections.
Result
- Distance10.00 km (6.22 mi)
- Ascent600 m (1,969 ft)
- Descent600 m (1,969 ft)
- Naismith base time2.00 hr horiz + 1.00 hr ascent = 3.00 hr
- Descent time penalty0.33 hr (1 hr per 1800 m descent)
- Fitness multiplier× 1.00 (naismith)
- Moving time3.33 hr
- Breaks30 min
- TOTAL elapsed3 hr 50 min
- Average moving pace3.00 km/h (1.86 mph)
Step-by-step
- Naismith base = (distance / 5 km·h⁻¹) + (ascent / 600 m·h⁻¹) = 2.000 + 1.000 = 3.000 hr.
- Descent penalty (Aitken/Langmuir) = descent / 1800 = 0.333 hr.
- Apply fitness factor 1.00: moving time = (3.000 + 0.333) × 1.00 = 3.333 hr.
- Add 30 min breaks → total 3.833 hr = 3 hr 50 min.
How to use this calculator
- Distance: trail-projected horizontal length (your map distance, not "as-the-crow-flies"). Convert miles → km by multiplying by 1.609.
- Ascent / descent: read from a topo map, GPX file, or guidebook. AllTrails / Komoot / Strava export gives these directly.
- Pick fitness honestly — the difference between "good" and "fair" Tranter is 35% on long routes.
- Add 30-60 min for breaks on day hikes; 60-90 min for half-day; 90+ min if you stop for photos.
About this calculator
Naismith's rule (William W. Naismith, 1892) is the workhorse hike-duration estimator used by Scottish mountain clubs, Britain's OS map system, and most hiking guidebooks: allow 1 hour per 5 km (3 mi) of horizontal distance plus 1 hour per 600 m (2,000 ft) of ascent. The base rule assumes reasonable fitness with a light pack on good ground. Tranter's corrections (Philip Tranter, 1949) extend it for individual fitness levels — measured by how long you take to complete the standardised 2-mile-plus-500-ft test. Modern refinements (Aitken, Langmuir) add a small descent penalty (≈1 hr per 1800 m descent) — descending is faster than ascending but slower than the flat. This calculator combines all three corrections plus a separate break-time line. Real-world calibration: most hikers find Naismith optimistic by 10-30% on rough terrain or with heavy packs; the Tranter "fair" and "poor" presets capture that drift.