Elevation Gain Time Cost Calculator
Enter a course's distance, total elevation gain and loss, your flat pace, and the average grade of the climbs and descents. You get the added time, the course time versus a flat equivalent, and how much of the distance is climbing or descending.
Elevation unit
Defaults to match the gain, for an out-and-back or loop course. Edit it for a point-to-point course that finishes higher or lower than it starts.
4% is a reasonable default for a rolling trail or road course. Raise it for a steep, switchbacked climb, and lower it for a long, gradual grade, since this one number sets how much of the course counts as climbing versus flat.
Added time versus flat
Course time: 3:35:10 vs. flat time: 3:30:59.
Climbing: 12.50 km. Descending: 12.50 km.
This estimate uses a generic formula. Connect your Strava/Whoop/Garmin data for a version personalised to your actual training.
Get early accessWhy total elevation changes a finish time
A flat pace does not survive contact with a hilly course. Every metre of climbing and descending runs at a different effective pace than the flat, so a course described only by its distance and total elevation change still hides a real time cost (or, on a net-downhill point-to-point course, a real time saving) that a single flat pace does not show.
How it is calculated
This calculator turns total gain and loss into climbing and descending distance by dividing each by the average grade you enter (gain ÷ grade = climbing distance, and the same for loss), then runs the remaining distance flat. Each portion is priced using the same empirical grade-pace factor as the Grade-Adjusted Pace Calculator. It is a simplification: real courses mix many grades rather than one constant climb and descent angle, so treat the result as an estimate, not a guarantee.
How to use the result
Use the added time to set a realistic goal on a hilly course from a flat-pace fitness number, and the climbing/descending breakdown to sanity-check the average grade you entered against what you know of the course. If you do not know the real average climb grade, 4% is a reasonable default for rolling trail or road; a steep, switchbacked climb runs steeper than that, and a long, gradual grade runs shallower.
Sources and limitations: see our methodology.
Worked example
Take a 10K loop with 200 m of gain and 200 m of loss at a 4% average climb grade, run at a flat pace of 5:00 /km.
That puts 5.0 km climbing and 5.0 km descending, with the rest flat. The flat-equivalent time for 10K at 5:00 /km is 50:00, but this course actually runs 51:41, 1:41 slower, because the quadratic grade penalty on the climb outweighs the smaller benefit on the matching descent.
FAQ
How much does elevation gain slow down a race?
It depends on how steep the climbing is and how much of the course it covers, not just the raw gain in metres. This calculator turns your total gain and loss into climbing and descending distance at the average grade you enter, prices each at the matching grade-adjusted pace factor, and reports the difference against running the same distance flat.
Does more elevation gain always mean a slower time?
Usually, but not always. The quadratic grade model means a climb always costs more time than the matching descent saves at the same grade, so a loop or out-and-back with equal gain and loss is always net slower than flat. A net-downhill, point-to-point course (more loss than gain) can come out net faster than flat.
What average climb grade should I use if I don't know the real one?
4% is a reasonable default for rolling trail or road running and is what this calculator starts with. Use a higher number for a short, steep, switchbacked climb, and a lower one for a long, gradual grade: the average grade sets how much of the course this calculator treats as climbing versus flat, so it matters more than the total elevation figure alone.
Why do I need to enter elevation loss separately from gain?
Because climbing and descending are priced differently. A loop or out-and-back has equal gain and loss, so the field defaults to match your gain automatically. A point-to-point course that finishes higher or lower than it started has unequal gain and loss, and entering the real numbers matters for an accurate estimate.
Is this the same as grade-adjusted pace?
It uses the same underlying grade-pace model as the Grade-Adjusted Pace Calculator, but answers a different question: that calculator converts one pace on one grade, while this one estimates the total time cost of a whole course's elevation profile from its distance, gain, loss, and average grade.