Crop vs resize: which one your image needs
Cropping chooses what’s in the picture; resizing chooses how many pixels it has. When to use each, what happens when the shape changes, and the right order.
· 4 min read
“Make it smaller” can mean two different things. Sometimes the picture has too much in it: a stranger at the edge, a wide sky over a small subject. Sometimes it has too many pixels: a 4000-pixel photo for a 1200-pixel space on a web page. The first is a job for cropping, the second for resizing, and mixing them up is how photos end up squeezed or blurry.
Cropping: choosing what’s in the picture
Cropping cuts away part of the image and keeps the rest exactly as it was. Every pixel inside the crop stays at full resolution, so a crop of a 4000 × 3000 photo that keeps the middle half is 2000 × 1500 pixels of the original detail.
Crop when you want to:
- remove something at the edge of the frame;
- bring the subject closer, or straighten the composition by the rule of thirds;
- change the shape: square for a profile picture, 4:5 for an Instagram post, 16:9 for a slide or thumbnail.
Cropping can’t make a photo larger, and a tight crop of a small photo leaves few pixels. A face cropped from a group shot may be only a few hundred pixels across, which looks soft when shown big.
Resizing: choosing how many pixels it has
Resizing scales the whole picture to more or fewer pixels and keeps everything in it. Shrinking is the common case and costs nothing visible when the result is still as large as it’s shown: a 4000-pixel photo shown 1200 pixels wide looks the same at 2400 pixels, which also covers high-density phone screens, and its file is a fraction of the size.
Enlarging works the other way and has limits. Software can invent smooth pixels between the real ones, but not detail that was never captured, so a photo enlarged more than about one and a half times starts to look soft. Graviton allows up to 4× and 8K (33 megapixels) and says when a picture is enlarged that far.
When the shape changes
Resizing to an exact width and height of another shape, say a landscape photo to a 1080 × 1350 portrait post, needs a decision, because the picture can’t fill the size without changing. There are three honest answers:
| Way | What you get | Use it for |
|---|---|---|
| Crop to the shape | The size filled; the edges outside the shape are cut | Social posts, thumbnails, banners |
| Add bars | The whole picture, with bars of a solid colour where the shapes differ | Products, artwork and documents where nothing may be lost |
| Stretch | The whole picture, distorted to fit | Textures and patterns, where distortion doesn’t show |
Stretching faces and buildings is the mistake people notice first: circles become ovals. When in doubt, crop, and move the crop so the subject stays in.
Doing both, in the right order
Crop first, then resize. The crop decides what’s in the picture, and the resize scales that to the size you need. Done the other way, you crop pixels you’ve already thrown away, and the result may come out smaller than planned.
Quality also depends on doing it in one step. Every time a JPG is saved it loses a little, so cropping in one app, saving, then resizing and saving again costs twice. In Graviton, the crop and the resize are applied together from the original and saved once, at the quality you choose.
A quick way to decide
- Is there anything in the picture you don’t want, or is the shape wrong? Crop.
- Is it much larger than the space it’ll be shown in, or does a site ask for a size in pixels? Resize.
- Does a site ask for an exact width and height? Resize to it and let it crop to the shape, then move the crop to keep what matters. In Graviton, the common sizes such as Instagram and Full HD do this for you.
Crop and resize in your browser
Graviton does both on your own device, without uploading the photo. Tap Crop above the image to drag a frame or pick a shape; turn on Resize to drag the image’s corners, type pixels or pick a size. The width and height always describe the cropped picture you’ll download. A whole batch can share one crop and size, with any image cropped on its own. Trying it is free and needs no account; downloading takes a free account with 3 downloads a day.