Because every website and mobile app has their own layout, it’s a job of social media sites to crop uploaded images according to their design/layout. Whether you’re creating a profile on Facebook, YouTube, Google+ or Twitter, a display picture and cover photo is must on your profile. Whenever you upload a new image on your profile, it will automatically or manually crop for the fit resolution.
As a common user, I never care about profile picture dimensions, but as a designer, I will love to know what are the dimensions of social media images. If you have some designing skills, you can easily merge any image in any resolution.
As of January, 2017:
Facebook Image Sizes/Dimensions
All dimensions written on this page as WidthxHeight.
Profile Picture: 170×170 pixels (But should be uploaded 180×180 pixels).
Profile Cover Photo: 851×315 pixels.
Page Cover Photo: 820×312 pixels.
Native Post Images: 720, 960 or 2048 pixels wide.
Link Thumbnail: 1200×630 pixels (Large), 600×315 pixels (Small)
Profile Picture Icon on Timeline: 40×40 pixels.
Twitter Image Sizes/Dimensions
Profile Picture: 400×400 pixels.
Header Photo: 1500×500 pixels.
Native Tweet Images: Minimum 440×220 pixels, Maximum 1024×512 pixels.
Link Summary Card: Minimum 280×150 pixels (Summary Card with Large Image), 125×125 pixels (Summary card)
Profile Picture Icon on Timeline: 48×48 pixels.
YouTube Image Sizes/Dimensions
Channel Icon: 800×800 pixels.
Channel Art: 2560×1440 pixels.
Video Thumbnail: 1280×720 pixels.
Channel Icon in Video Page: 48×48 pixels.
Instagram Image Sizes/Dimensions
Profile Picture: 110×110 pixels.
Post Image: Maximum 1080×1080 pixels.
Profile Picture Icon in Feed: 28×28 pixels.
LinkedIn Image Sizes/Dimensions
Profile Photo: 400×400 pixels.
Background Photo: 1000×425 pixels.
Hero Image: 974×330 pixels.
Direct Shared Image on Home: Maximum width 1024 pixels.
Shared Link Thumbnail: 190×100 pixels.
Profile Picture Icon on Home: 80×80 pixels.
Google+ Image Sizes/Dimensions
Profile Picture: 250×250 pixels.
Cover Photo: 1080×608 pixels.
Direct Image Shared on Home: Maximum width displayed 530 pixels.
Shared Link Thumbnail: Maximum 506×211 pixels.
Profile Picture Icon on Home: 36×36 pixels.
Pinterest Image Sizes/Dimensions
Profile Picture: 165×165 pixels (Recommend upload 600×600).
Cover Image: 217×147 pixels.
Pinned Image at Home: Maximum width displayed 235 pixels.
Profile Picture Icon on Home: 51×51 pixels.