How To Size Your Images So They Show Their Best on Facebook
How can I make sure that my photos display in the highest possible quality?
Regular photos 720 px, 960 px, 2048 px
If you use a 2048 px photo, make sure to select the High Quality option when you upload it.
To avoid compression when you upload your cover photo, make sure the file size is less than 100 KB. Save your image as a JPEG with an sRGB color profile.
Facebook Photos Size Guide / 2014
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