Here’s a quick guide on news feed image sizing for some of the most popular social media platforms.
470×394. Facebook will not crop, it will scale. Upload images with widths of 720, 960, or 2048 pixels for optimal quality, and Facebook will resize images automatically to fit the feed.
640×640. Think square, not landscape or portrait. Photos uploaded to Instagram can be a maximum of 2048×2048 pixels.
506×253. Think more landscape. Images pixels can be up to 1024×512.
350 minimum width. Since Google+ uses lots of columns, height varies. Google+ lets you see the full image when clicked, so bigger images do well.
238 pixels wide. Like Google+, Pinterest uses lots of columns in their newsfeed, creating a wide variation in image height. When expanded, the images will appear 735 pixels wide.