Corrupt FIT file - online repair tool won't work and i'm on a Mac

The file is 96 KB. Fit File Repair tool returns the message "87676 bytes of the file are corrupted and could not be repaired." Essentially over 90% of the file is corrupt. 

Could you give us some background on this? Which Garmin did you use? Anything unusual happen during the activity? When you finished the activity, were you able to press stop, then save? Is it viewable normally in your device's history?

Some tips to help minimize the occurrence of corrupt fit files:

• Keep the number of files in the \GARMIN\ACTIVITY folder on the device’s file system to a minimum using these directions: Removing Recorded Activities on a Garmin Fitness Device If you delete the files in your activity folder with a Mac computer, then empty the trash folder before you unplug your device from the computer.
• Try to avoid excessive button presses during your activity.
• Regularly check for firmware updates.
• If issues with corrupt files persist, contact Garmin Support.

seilogramp said:

The file is 96 KB. Fit File Repair tool returns the message "87676 bytes of the file are corrupted and could not be repaired." Essentially over 90% of the file is corrupt

This file again is a block of 6 different FIT files (6 different file headers in the same file). They need to be splitted into individual files, using a hex editor, and then perhaps either can be merged correctly, or some data can be restored from them individually.

Was the data block restored with Recuva or a similar tool? It is not a standard FIT file (can have only a single file header)

The offsets of the individual blocks are at 0x00000, 0x14400, 0x14800, 0x15800, 0x15C00, and at 0x16000

If the FFRT can extract the data starting at that offset, you can use the info

Attached the 6 individual parts: chunks.zip

Gah 90% haha :( I used a Venu SQ. Nothing unusual happened really but i was able to press stop and save. It's viewable on the device but I couldn't upload it to my account. It was supposed to be a run but it turned into a 2+ hr walk haha.

Thanks for the tips. Will clear my activity folder when I get home!

Ohhh thanks for this but how do i use this? :( So sorry, I'm a new garmin user (just 3 months? 4?) and have no idea what i'm doing right now

Well, you can try fixing them individually, or merging them first, and then fixing the merged file. You can try different permutations when merging them, though I'd start with the same order as the numbers of the chunks, first. Or you can just try looking what is inside them. But all of it requires some experience with repairing FIT files, and some tools too. And some time, of course, too.

Or you can hope someone else sees it here, and does it for you.

Or you just go over, and go out and do the run or walk again, instead. I'd tell it would be a better spent time