Tools
FIT File Analyzer
What This FIT Analysis Shows About Your Race
Upload a FIT file from your sports watch and see how you actually paced your effort across the course. This FIT file analyzer turns your running data into a clear, practical overview: distance, time, elevation gain and loss, pace, heart rate, elevation profile, VAM on climbs, pace by gradient and efficiency on flat sections.
Drop your .fit file here
or
Your file never leaves the browser. All analysis runs on your device.
Elevation profile + heart rateVAM on climbsPace by gradePacing verdict
What you'll see in the analysis
Elevation profile + heart rate
See how your heart rate responded to every climb and descent.
VAM on climbs
Vertical speed for every detected climb, compared side by side.
Pace by grade
Where you gain or lose time on descents, flats and climbs.
Pacing verdict
A plain-language read on whether you started too hard or paced it well.
The tool is built for trail runners, mountain runners and ultrarunners who want useful insights without getting lost in overly complex dashboards. It helps you understand where the course was most demanding, whether you started too hard, how your heart rate responded to climbing, and where pacing, downhill technique or fatigue may have cost you the most energy.
FIT file analysis can help you prepare better for your next race, improve your pacing strategy and train more specifically for trail running, mountain races and ultramarathon performance.
How to read this trail running analysis
Elevation profile and heart rate
The upper layer of the chart is the course shape, and the overlaid heart rate shows how your body responded to each climb and descent. Look for places where heart rate rises faster than the terrain, which is often a sign of a section run too hard or of mounting fatigue.
Pace by grade
Grade changes the cost of running in a nonlinear way. A pace of 12:00/km on a steep climb can be physiologically harder than 5:00/km on the flat, because climbing raises energy demand and cardiorespiratory load. So this chart does not judge speed directly, it shows how evenly you kept moving across different terrain.
The same is true of descents. Up to a certain grade, running downhill is cheaper than the flat, but on very steep descents the cost rises again, and the braking work of the muscles adds up.
VAM, your vertical climbing speed
VAM is the number of vertical meters climbed per hour. It shows well how hard you climbed on a given ascent and lets you compare climbs with each other. A VAM drop in the second half of a run usually means climbing fatigue or too hard a start.
An important limit: compare VAM only between climbs of similar steepness, length, and technicality. A gentle running climb and a steep power-hike are not directly comparable.
Frequently asked questions
- Is my FIT file sent anywhere?
- No. The entire analysis runs in your browser, the file never leaves your device, and it is not sent to any server.
- Which watches do FIT files work from?
- From most watches and sports apps, including Garmin, Coros, Suunto, Polar, and Wahoo. A .fit file from a running activity is all you need.
- What is VAM in running?
- VAM is climbing speed expressed in vertical meters per hour. It shows how fast you gain elevation on a climb and is best compared between climbs of similar steepness.
- Why does my uphill pace look so slow?
- Because running uphill is far more energetically expensive than the flat. A slow pace on a steep climb can correspond to a very hard effort. That is why we look at pace by grade rather than only raw min/km.
- Do I need a chest strap?
- It is not required, but it gives more faithful heart rate. A wrist optical sensor can be less accurate during variable trail effort, so heart rate interpretation is more reliable with a chest strap.
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