Exact dimensions for Instagram, YouTube and Facebook, and how to avoid awkward automatic cropping.
Every social platform expects a different image shape, and getting it wrong means the platform crops your photo automatically — often cutting off exactly the part you cared about.
Instagram square posts are 1080x1080px, portrait posts are 1080x1350px, and Stories or Reels use a full-screen 1080x1920px. YouTube thumbnails are 1280x720px at a 16:9 ratio. Facebook cover photos are 820x312px on desktop (though it renders slightly differently on mobile), and profile pictures across most platforms are safest as a square, at least 400x400px so they don't look blurry when platforms scale them up.
When you resize a photo to fit a different aspect ratio than the original, something has to give — either the whole image shrinks to fit (leaving empty bars) or it gets cropped to fill the frame. For most photos, cropping evenly from the center keeps the main subject in frame, since people, products, and focal points tend to be centered in the original shot. It's not perfect for every photo, but it's a solid default.
If your original photo is heavily compressed already or very large in file size, resizing first and compressing after tends to give a cleaner result than doing both at once. Start with your best-quality original, resize to the platform's exact dimensions, then compress lightly if the platform has its own upload size limit.
Instagram post: 1080x1080. Instagram Story: 1080x1920. YouTube thumbnail: 1280x720. Facebook cover: 820x312. When in doubt, square (1:1) is the safest fallback that displays reasonably across almost every platform without awkward cropping.