With the layouts, designs and specs of social media sites undergoing regular updates and modifications, business owners struggle to play catch-up (“That danged Facebook Timeline!”).
Here’s the lowdown on sizing your graphics for the various social media sites you might be using. [Note: Image dimensions are given in pixels, width X height. Different sites have different file size limitations
Google+
For your header photo, Google allows either a single panorama image (940X180 pixels), or a strip of 5 scrapbook pictures (110X110 pixels each). Your profile picture – which is separate – should be 250X250 pixels.
Facebook
Facebook’s Timeline cover photo is 851X315 pixels. The profile picture recently changed to 160X160 pixels (on 4/26/12). Custom photo tab images are 112X75 pixels.
Twitter
Twitter’s profile pictures should be perfectly square. The pixel measurements are not as important since the image will scale, but note that rectangular images will be cropped.
LinkedIn
As with Twitter, LinkedIn uses square pictures that it resizes for various uses (a 40X40 pixel thumbnail, an 80X80 pixel photo and a 400X400 pixel “zoom” mode).