Hi,
i got the following error message today when i wanted to upload my 2 FIT files (484kbyte and 617kbyte):
413 Request Entity Too Large
nginx/1.17.8
Can You fix it?
Curious, why are you uploading two fit files? Zwift already has the .fit file from the device you used during the ride (e.g., trainer). You would then only need to upload the .fit file from your secondary power source (e.g., pedals, crank spider).
@Lin_Alan because i´m using this dual analysis service for more advanced power meter comparisons than a Zwift race, so simple. And just for info, if You are running the Zwift on an Ipad or older/slower device, the Zwift´s FIT file will be shorter (in time) than the reality (and the comparison will be inaccurate), so better to record a Zwift race with 2 head units for the 2 power sources (and ignoring the Zwift´s original FIT file). And somebody has 3 power sources so that is 3 FIT files.
but i could solve the problem, i removed the GPS datapoints (and every unnecessary datafields) from the FIT files and i could upload these smaller files already.
i sent an email to zwiftpower@zwift… about this issue after 5years, but no response, can somebody fix this server??? increase that file size limitation to 2MByte per file , the actual one is very low (i suppose 500Kbyte per file or 1MByte in total, i couldnt determine it exactly )
5 years later
I don’t know if there’s a reason why increasing the limit would be complicated but I do know that ZwiftPower is getting little to no development so any change would be quite unexpected.
better late than never! 
I’m afraid that this won’t be something that we would fix as ZwiftPower is end of life as we move to a replacemement under zwift.com.
Here’s an alternative that you could try if what you want is the analysis…
DCRainmaker Analyzer for a nominal cost: DCR Analyzer Tool Overview & Manual
i know both and i use the c-t-w daily (i wrote a few tips to the developer in the past, probably i will do it again just he has no time/mood to develop that further as last time he said to me) just the zwiftpower has a nice and easy UI (but it cant show the balance with dual pms)