Assess an ascent profile and the effect of altitude on performance.
Aerobic capacity falls about six per cent per thousand metres above 1,500, so ascent rates slow with height even on easier terrain. Oxygen availability follows the barometric pressure curve rather than falling linearly. Underestimating the altitude penalty is why summit day routinely takes half again as long as the gradient alone suggests.
Mountain Elevation
Ascent time = elevation gain ÷ ascent rate, reduced by the altitude penalty
Ascent time = elevation gain ÷ ascent rate, reduced by the altitude penalty Aerobic capacity falls about six per cent per thousand metres above 1,500, so ascent rates slow with height even on easier terrain. Oxygen availability follows the barometric pressure curve rather than falling linearly.
Underestimating the altitude penalty is why summit day routinely takes half again as long as the gradient alone suggests.
This calculator takes 4 inputs: Summit elevation, Trailhead elevation, Distance to the summit, Ascent rate at low altitude. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.