Inspect an activity file

Not every question about a file is a question about fixing it — sometimes you just want to know what's actually inside before you trust it for something else, and inspect is built purely for that: it's a viewer, not an editor, and it never changes a single byte of what you feed it. Drop in a file and it lays the route out on a map, plots a time-series chart for every sensor channel the file actually contains — heart rate, cadence, power, elevation, whatever was recorded — and breaks the activity down into per-lap summaries where lap data exists. Below that sits a raw field table listing every value the file holds, including manufacturer-specific or otherwise unrecognized fields that FitFileHub's own converters don't interpret or expose anywhere else on the site; if you've ever wondered what a FIT file actually contains beyond the handful of channels every tool talks about, this is where you'd see it. The practical use cases tend to cluster around confirmation rather than exploration for its own sake: checking that a repair actually caught what you expected it to, confirming a merge lined up two files correctly at the seam, or just sanity-checking a file someone sent you before importing it into a training platform you'd rather not feed garbage data into. Because nothing is written or altered, there's no risk in opening a file just to look — inspect can't damage it. As with every tool here, the file is parsed and rendered entirely inside your browser; viewing it never means uploading it anywhere. Works with FIT, GPX, TCX, CSV, and GeoJSON, free for files up to 25 MB.