How long does an 800 m ascent take?
Elevation gain alone does not determine walking time. For 8 km, 800 m of ascent and no descent, at standard pace with no pack, Naismith gives 2 h 56 min and DIN 33466 gives 3 h 40 min. Add breaks separately.
Three methods and adjustable assumptions
Naismith adds distance at 5 km/h and ascent at 600 m/h, with no descent correction. DIN 33466 uses 4 km/h, 300 m/h up and 500 m/h down: add half the shorter horizontal/vertical time to the longer one. Tobler uses v = 6 × exp(−3.5 × |s + 0.05|), where s is signed rise over horizontal distance.
Without a track, Tobler divides the distance between ascent and descent in proportion to their elevation totals and uses a constant gradient for each part. With GPX it sums segment times. Pace scales speed for all three methods. The optional pack adjustment multiplies time by 1 + pack weight / body weight; this is a separate user adjustment, not part of the original formulas.
Importing a GPX track
The file stays in your browser. Distances use WGS 84 geodesics; ascent and descent sum consecutive elevation differences within each track segment. Separate segments are never joined. Every point must have elevation. GPS noise can inflate elevation totals; no smoothing or terrain correction is applied. Estimates exclude breaks and depend on trail conditions and individual ability.
Frequently asked questions
Does accumulated ascent mean summit elevation?
No. Add every climb along the route. A route that climbs 400 m, descends 200 m and climbs another 400 m has 800 m of ascent and 200 m of descent.
Why do the methods give different times?
They use different reference speeds and ways of accounting for slopes. A GPX profile improves Tobler’s gradient estimate; total ascent alone cannot describe the terrain.