The Correct Image Sizes for Every Social Platform in 2026
Every major social platform expects images at a specific aspect ratio, and getting it wrong doesn't just mean the image looks slightly off — it means the platform decides what to crop out of your image for you, based on an algorithm that has no idea what's actually important in the frame.
Crop and resize in your browser (no upload, free)
The Social Image Resizer on keptlocal center-crops and resizes a photo to any of six platform presets, entirely on your device.
Reference dimensions
| Platform | Dimensions | Aspect ratio |
|---|---|---|
| Instagram Post | 1080 × 1080 | 1:1 (square) |
| Instagram Story | 1080 × 1920 | 9:16 (vertical) |
| X / Twitter Post | 1600 × 900 | 16:9 |
| Facebook Post | 1200 × 630 | ~1.91:1 |
| LinkedIn Post | 1200 × 627 | ~1.91:1 |
| YouTube Thumbnail | 1280 × 720 | 16:9 |
What happens when you upload the wrong size
Platforms handle a mismatched aspect ratio one of two ways: crop, or letterbox. Cropping is more common and more risky — the platform's algorithm picks what to trim based on general heuristics (often centering on detected faces, if any), with no understanding of what matters in your specific image. A product shot with the product off to one side, a screenshot with important text near an edge, or a group photo with someone at the frame's border can all lose exactly the part that matters. Letterboxing (adding bars to preserve the full image) is safer for content but produces a smaller, less visually prominent result surrounded by empty space — rarely the outcome anyone actually wants for a feature post.
Design at the target size, not up to it
Always work from an image at least as large as the target dimensions, then resize down. Enlarging a smaller image to hit a target size requires the resize algorithm to invent pixel detail that was never captured, producing a visibly softer result — the same reason a small phone photo blown up to billboard size looks blurry rather than sharp. Shrinking, by contrast, discards data you don't need and looks clean at any reasonable ratio.
Why Instagram's two formats differ so much
Instagram Post (square, 1:1) and Instagram Story (vertical, 9:16) reflect two genuinely different viewing contexts within the same app. Posts live in a scrollable feed and a grid-view profile page, where a square format has historically balanced well against both landscape and portrait source photos without excessive cropping either way. Stories and Reels take over the entire phone screen — a vertical format fills that space completely, while a square or horizontal image would leave the top and bottom of the screen empty or force an awkward crop.
Privacy: what happens to your image
Cropping and resizing both run on an HTML5 canvas in your browser — your image is never uploaded before you're ready to actually post it.
Resize for any platform now with keptlocal's free Social Image Resizer — no upload, no signup.
Frequently asked questions
What happens if I upload the wrong size?
Do these dimensions change often?
Should I design at a higher resolution and scale down, or exactly at the target size?
Why is Instagram Story a different aspect ratio from Instagram Post?
Can I use the same image for multiple platforms?
Crop and resize to the exact size each platform expects — free, in your browser.
No upload. No signup. Runs in your browser.