You're faster than you think. Convert your elevation gain into flat-equivalent speed.
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Distance
-- km
Avg Pace
--:-- /km
Time
--:--:--
Elevation
-- m
Effort Distance
-- km
Grade Adjusted Pace
--:-- /km
Now that you know your effortless pace, use our Route Planner to estimate how long your next mountain run will take.
Grade Adjusted Pace estimates the equivalent pace on flat land for a given effort on hilly terrain. Running uphill requires significantly more energy than running flat, so your "real" pace is faster than your watch shows.
Conversely, running downhill is usually faster / easier (energetically), until the grade becomes too steep (-20%), at which point braking forces increase the energy cost again.
We use the Minetti (2002) energy cost formula, a standard in sports science. We analyze your GPX file segment by segment, calculating the gradient for each step, and applying an "Energy Cost Factor" multiplier to the distance.
Both TrailSplits and Strava use variants of the Minetti energy cost model, so results are typically within 2–5% of each other. The main differences come from how each tool smooths elevation data and handles GPS noise. TrailSplits processes your raw GPX file directly in your browser, giving you full transparency into the calculation.
The Minetti formula was calibrated for running, but the relative energy costs hold directionally for fast hiking. At walking speeds, the absolute numbers are less precise, but the comparative insight — "this route was X% harder due to terrain" — remains useful for planning and comparing hikes.
GAP accounts for the extra energy cost of climbing and the reduced cost of moderate descents. If your trail run had significant elevation gain, your GAP pace will be faster than your watch pace, showing that your flat-equivalent effort was actually quite strong. Conversely, a mostly downhill run will show a slightly slower GAP because gravity was helping.
Yes. Your GPX file is processed entirely in your browser using JavaScript. No data is uploaded to any server. TrailSplits never sees, stores, or transmits your file. This applies to all our GPX tools.