Drop in a file from your running watch and read what actually happened during the run: what changed, where it changed, and what might account for it. Run Log reads FIT and GPX files, shows moments rather than averages, and shows its working for every claim it makes.
Nothing is uploaded. There is no account and no server — your file is parsed by your own browser and stays on your own machine. Run Log is free and open source.
Run Log needs JavaScript to read and draw a run, so please enable it to use the app.