I have had some people approach me with huge FIT files. A FIT file that is larger than ~2.5 Mb is very big. A FIT file larger than ~10 Mb is HUGE, and a FIT file larger than ~20Mb probably isn't going to work on most platforms; it's just too much data to handle. A lot of data-hungry people put their devices on 1s recording so they can see every second of their activity. This is great for your 30 minute lunch workout, but it becomes onerous if you're trying to string together your multi-day adventure race. GOTOES can fix that, though, by thinning out your file.
To get to the FIT File Shrinking tool, click here.
The way the tool works is that you upload your FIT file, and GOTOES searches for the most abundant message type (typically the records - the ones that include your position, heart rate, cadence, power, etc.). GOTOES lets you specify how much data will be removed and how much smaller your file will become. Your goal is to get your FIT file down to about 2Mb. So, if you have a 24Mb file, you're going to want to select the "Every 10th record (90% reduction)" option. If your file is only 10Mb, you might be able to get away with only discarding half of the data... Feel free to try different options.
If your file is too big for even GOTOES's generous upload limits, use the contact form and let me know so I can temporarily allow you a higher upload limit. I need to prevent the server from being overloaded by massive uploads, so this would be on a one-time-use basis.
Hope that helps you out!!
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