Every few months someone asks me why their Instagram photo looks blurry or their YouTube thumbnail has its title cut off at the edge. The cause is nearly always the same: the picture was not made for the space the platform puts it in. Platforms then crop it, shrink it or recompress it, and the result looks worse than the original. Getting the size right before you upload gives you control over what people actually see.
Two ideas that explain most problems
Aspect ratio is the shape of the picture, such as 1:1 for a square or 16:9 for a widescreen frame. Pixel size is how many pixels wide and tall it is. Platforms care about the shape first, because a wrong shape means cropping. Pixel size matters second, because too few pixels looks soft, and far too many gets recompressed anyway.
Sizes that work well right now
Platforms change their layouts from time to time, so treat these as reliable starting points and check the platform’s help page if something looks off.
- Instagram post: 1080 x 1080 (square) or 1080 x 1350 (4:5 portrait). The portrait shape takes up more room in the feed, which is why many creators prefer it.
- Instagram Story and Reels: 1080 x 1920 (9:16).
- YouTube thumbnail: 1280 x 720 (16:9), under 2 MB.
- YouTube channel banner: 2560 x 1440, keeping important content in the centre safe area.
- Facebook post: around 1200 x 630 for link-style images, or 1080 x 1350 for portrait photos.
- LinkedIn post: around 1200 x 627 for a shared image.
- X (Twitter) post: 1600 x 900 (16:9) displays cleanly in the timeline.
- Pinterest pin: 1000 x 1500 (2:3), because tall pins use more space.
Safe zones: the part people forget
Even with the right size, apps cover parts of the image with their own interface. On a Story, the top and bottom are partly hidden by your profile name and the reply box. On a YouTube thumbnail, the video length badge sits in the bottom-right corner. If your text lives in those areas, it disappears. Keep the important parts, especially words and faces, in the middle two-thirds of the frame. When I design a thumbnail, I place the title on the left side and keep the bottom-right corner empty for that reason.
Resize first, then upload
If you upload a 4000-pixel photo, the platform shrinks it with its own compression, which you cannot control. Doing it yourself gives better results, and also makes the upload quicker on mobile data. The Image Resizer includes presets for these sizes, and it can make several of them from one photo in one go. If the framing is the issue rather than the size, use the Image Cropper and choose the ratio first, so you can decide what is left in the frame instead of letting the app decide for you.
Why it still looks soft after uploading
Most platforms recompress every image you upload. Small text, thin lines and fine textures suffer most. Three habits help: export at high quality (85 to 90 percent for JPG), avoid tiny text, and do not upload a file that is already low quality, since the platform will make it worse. Screenshots with small writing are the usual victims. If you must post one, enlarge the text before capturing.
Profile pictures behave differently
Profile photos are cropped into a circle on almost every platform, even though you upload a square. That circle cuts off all four corners, so a logo with text near the edges loses letters. Place your face or logo well inside the centre, and leave generous margins. Upload a square at least 400 pixels wide, because the same image gets reused at many sizes, from a tiny comment avatar to a large profile header.
Dark mode and backgrounds
Many people browse in dark mode now. A logo with a transparent PNG background may look fine on white and vanish on black. Check how your image looks on both before you commit, or give it a solid background of its own so it looks the same everywhere.
A quick example
Say you have one photo from a family function and want it on Instagram, Facebook and Pinterest. Cropping once to 4:5 and resizing to 1080 x 1350 covers Instagram and Facebook together. For Pinterest, crop the same photo to 2:3 and resize to 1000 x 1500. That is two exports instead of a different struggle on every platform.
Building a small habit around it
- Decide the platform before you edit, not after.
- Keep one full-size original, and create smaller copies from it.
- Name the copies clearly, for example “festival-ig-4×5.jpg”.
- Look at the result on your phone before posting, because that is how most people will see it.
The numbers above will change over time, but the method will not. Know the shape, respect the safe zone, resize before uploading, and your pictures will appear the way you intended.