There are several features of Facebook’s layout to keep in mind, but the biggest ones are the cover photo and the profile photo.
The cover photo is the big photo prominently displayed on a person’s profile. Currently, it is 820 x 312 pixels. To keep your image looking good and to keep it from getting cut off, make sure the actual image in your cover photo is 667 x 176 pixels.
Next to the cover photo is your profile picture. It is displayed on the profile and also pops up in a thumbnail size next to comments and posts you make. At its full size on your profile, it is 160 x 160 pixels. However, it will display as 180 x 180 pixels. In its thumbnail size, it is 32 x 32 pixels.
The cover image and profile picture are once again the two most important images to get right.
The cover photo on Google Plus is a lot bigger than the one on Facebook and the profile picture is much smaller. The cover photo is 1080 x 680 pixels and the profile picture is 250 x 250 pixels. However, the profile thumbnail is bigger than Facebook, at 150 x 150 pixels.
The profile picture on Twitter is 400 x 400 pixels. Its thumbnail is 48 x 48 pixels. The cover photo is 1500 x 1500 pixels. But there are other important sizes for Twitter’s layout. Shared photos and video and photo preview are all important. You want to make sure your tweets look good and fit the dimensions, not sloppy. Image preview is 60 x 60 pixels. Shared images are 590 x 295 pixels. Shared videos are 483 x 274 pixels.
Even though photos are what makes up Instagram’s concept, it is important to also fill out the 150 character bio with its 100 character title to the best of your ability.
Shared photos are 161 x 161 pixels. Your profile picture is 110 x 110 pixels.
Your cover photo is the most important on this professional networking site. The smallest it can be is 200 x 200 pixels but ideally your photo is about 400 x 400 pixels. Your thumbnail will be 50 x 50 pixels.
Your profile picture is 165 x 165 pixels. Your title is 100 characters long and your description is 200 characters long. Large thumbnails is 222 x 150 pixels. Smaller thumbnails are 55 x 55 pixels.
The pixel size changes depending on if it is being viewed on tablet, TV or phone. But for your cover photo, 1,546 x 423 pixels are always visible with 507 pixels of flexible space to the right and left of the safe area.