Aspect ratio is the shape of an image or video written as width to height, such as 1:1 (square), 4:5 (portrait) or 16:9 (widescreen), whatever its size in pixels.
Crop and resize a photo to any platform's shape.
Also used in: Instagram Grid Maker, Photo Collage Maker, YouTube Thumbnail Checker & Resizer
Every platform shows images in particular shapes, and a photo in the wrong one gets cropped or shrunk with bars around it.
Instagram feed posts can be anything from 1.91:1 to 3:4 at 1,080 px wide, Reels and Stories are 9:16, and YouTube thumbnails are 16:9. Choosing the shape before cropping, rather than letting the app do it, keeps heads and horizons where you want them.
A photographer shoots in 3:2, the shape of her camera's sensor.
For Instagram she crops to 4:5, the tallest shape that also works in the feed on most phones; for the YouTube thumbnail of her behind-the-scenes video she crops the same frame to 16:9, moving the crop so the model's face stays in the left third clear of the timestamp.
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