A ride file cut off by a flat battery, a crash or a full memory can usually be rebuilt. Drop it here to check it, then download a valid FIT with every record that was saved. Your file is not uploaded.
Read in your browser. Your file is not uploaded.
A bike computer writes records as the ride goes, but it only writes the file's final size, the session summary and the closing CRC when you save the ride. If the battery dies, the unit freezes or the memory fills first, the file ends mid-record with a header that no longer matches its contents.
Strict readers reject a file like that, and upload pages can too, even though almost all of the ride is in it.
The records it keeps are copied byte for byte. Nothing is estimated, smoothed or filled in, so the repaired ride is exactly what the device recorded up to the point it stopped.
A device that switches off never writes its session summary. The repaired file then has every record but no summary, and the tool tells you so. Some platforms rebuild the summary from the records; others may still reject the file.
If a platform rejects the repaired FIT, download the same ride as TCX from the result panel. TCX carries laps, distance, heart rate, cadence, speed and power without needing a FIT summary.
The file is read by JavaScript running in this browser tab. It is never uploaded: there is no server on the other end that could receive it, and the page makes no network request with its contents.
You can check that yourself. Open your browser's developer tools, go to the Network tab and drop a file in. You will see the page's usual requests, such as the site's analytics and, the first time you open a FIT file, the file reader loading. None of them carries your file.
If the device stopped recording twenty minutes before it switched off, those twenty minutes are not in the file, and no tool can bring them back.
The repair keeps everything up to the first record that does not make sense. If a file is damaged in the middle rather than at the end, what comes after the damage is dropped, and the result says how many bytes that was.
GPX and TCX are text files and break in different ways; this tool only rebuilds the FIT binary structure.
Usually, yes. Most damaged ride files are cut off at the end because the device lost power before saving. Everything recorded up to that point is still in the file; the repair keeps it and rewrites the size and checksum so apps accept it again.
Only the incomplete bytes at the point where the file breaks, typically the last second or two. The result tells you how many records were kept and how many bytes were dropped. Anything the device never recorded cannot be recovered by any tool.
A file that ends mid-record, or whose size and checksum do not match its contents, fails the structural checks upload pages run. Repairing those three things is usually enough. If the platform still refuses it because the session summary is missing, download the ride as TCX from the result instead.
No. The repair runs in your browser tab and the file never leaves your computer. You can check it in your browser's developer tools: in the Network tab, none of the requests the page makes carries your file.
Then the problem is not the file structure. Common causes are an activity the platform already has (a duplicate), a sport type it does not support, or a file from a device it does not recognise. Opening the file in the FIT viewer shows what is inside.
