I never use the download sites on the first page cause I don't trust them, they always seem to have bigger files than needed, take for instance, gofile I think it said 6.5gb, yet someone put a link up for mega and the file size was only 5.8gb, so you tell me what that other 0.7gb was. I only use Mega, yes I pay for the benefit, but the amount I download off here it's worth it.
This is actually normal. The same file being hosted at 2 site may be described differently because some sites dont calculate the accurate size and simply use the "easy" marketing way of describing size as
1 gb = 1,000,000,000 b
instead of the true conversion of
1gb = 1,073,741,824 b
and your example is slightly off but close enough.
if GoFile is using the "easy" conversion then a 6.5gb file would convert accurately like so:
6,500,000,000 b = 6.0536 gb
And mega would use the Accurate conversion and show the file as 6.05 gb
The files are the same. Drive manufacturers use this simplified conversion in marketing all the time as do Cloud Storage providers