Recorded the same session on a watch and a bike computer? Copy heart rate, power, cadence, GPS or altitude from one file into the other, so one upload has the best of both.
Lining the files up
Two devices rarely agree on the time. The tool matches the files using speed, heart rate or power and lines them up automatically. A chart shows both traces on top of each other, with a slider to nudge the second file by a few seconds before you merge.
What to copy
The main file keeps its GPS, laps and summary unless you choose otherwise. Tick the data to copy from the second file, and averages and maximums are recalculated.
Quick answers
Why merge FIT files? A common case is a bike computer with good GPS and power, and a watch with the heart rate. Merging gives one activity with all of it, so your training load is right.
What if the clocks were minutes apart? The tool searches up to ten minutes either way to find the best match. Check the chart, adjust the slider if needed, then merge.
More free tools for your activity files are on the FIT file tools page.
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