Convert FIT to TCX a Garmin .fit activity as a TCX file, laps included

What the TCX file contains

• Activity

  Running, cycling or other, and the start time.

• Laps

  Start time, total time, distance, maximum speed, calories, average and maximum heart rate.

• Points

  Time, position when there is one, elevation, distance, heart rate and cadence.

• Speed and power

  In the ActivityExtension of each point.

TCX or GPX?

Choose TCX when the laps matter (intervals, a race split by kilometre) or when the activity has no GPS track, such as a treadmill run or a home trainer ride: every point is kept, with or without a position.

Choose GPX for maps and route planners. And to import into Garmin Connect or Strava, the FIT file itself remains the most complete.

TCX only knows running, cycling and “other”: a hike or a swim is written as “other”.

Example

The sample “Healthy bike ride” above the drop zone has 6 laps, so its TCX has 6 <Lap> blocks. The first one starts like this:

<Lap StartTime="2026-10-26T13:05:00Z">
  <TotalTimeSeconds>646</TotalTimeSeconds>
  <DistanceMeters>5002.8</DistanceMeters>
  <MaximumSpeed>9.235</MaximumSpeed>
  <Calories>65</Calories>
  <AverageHeartRateBpm><Value>143</Value></AverageHeartRateBpm>
  <MaximumHeartRateBpm><Value>157</Value></MaximumHeartRateBpm>
  …

Questions