Resize, compress or crop — pick the right one
These three jobs get mixed up, and using the wrong one wastes time.
- Resize changes the pixel dimensions: a 4000 × 3000 photo becomes 1600 × 1200. Use it when a site, form or app demands specific dimensions or a maximum size.
- Compress keeps the dimensions and lowers the file weight, usually by re-encoding a JPEG or WebP at a lower quality setting. Use it when the image is the right size on screen but the file is too heavy to send or upload.
- Crop removes part of the image to change its shape or framing. Use it when the proportions are wrong, not the resolution.
Many tasks need two of them. A profile photo for a form might need cropping to a square and then resizing to 400 × 400. Do the crop first, then the resize, so you are not scaling pixels you are about to throw away.
How resizing works
When you shrink an image, pixels are combined, and the result usually looks clean. When you enlarge, the software has to invent pixels that were never captured, so edges soften and fine detail turns mushy. A small image blown up to a large size will look blurry no matter which tool does it. If you need a big print or a large hero image, start from the largest original you have.
Resizing does not restore detail. If a photo is already soft, resizing it smaller can make it look sharper on screen simply because the flaws shrink with it.
Keep the aspect ratio
Aspect ratio is the relationship between width and height. A 3:2 photo stays 3:2 only if both numbers change by the same factor. Type a new width with the ratio lock on and the height updates automatically.
Turning the lock off lets you set any width and height, which stretches or squashes the subject. That is occasionally useful for fitting an exact box, but faces and logos usually look wrong. If you need a specific shape, crop instead of stretching.
Common sizes
| Use | Typical dimensions |
|---|---|
| Email attachment or quick share | 1200–1600 px on the long edge |
| Web page or blog image | 1200–2000 px wide |
| Social profile picture | 400 × 400 px or larger square |
| ID photo or online form | 600 × 600 px, often with a file size cap |
| Full-width banner | 1920 px wide |
These are starting points, not rules. Check the requirements of the site or form you are submitting to, because some ask for exact pixel values and a maximum file size.
Resizing by file size
Some uploads care about megabytes, not pixels. A phone photo is often 2–5 MB, while a form may accept only 1 MB. Switching to file-size mode lets you set a target, and the tool adjusts the dimensions and encoding to land near it. Expect a small drop in sharpness as the target gets tighter — that is the trade-off, and it is normal for JPEG and WebP.
What you get
The output keeps the file type you started with unless you choose otherwise. PNG is better for screenshots, logos and anything with flat colour or transparency. JPEG is smaller for photographs. WebP is often smaller still and is widely supported in browsers.
Everything happens on your device. Images are never uploaded, nothing is stored, and the tool keeps working if you go offline after the page has loaded. There is no account to create and no watermark added to your result.
Questions
Does resizing an image reduce its quality?
Making an image smaller usually looks fine because pixels are merged. Enlarging softens detail, since new pixels are estimated rather than captured. Saving as JPEG or WebP also re-encodes the file, which can introduce slight compression artefacts.
Are my images uploaded to a server?
No. The tool runs entirely in your browser, so the file stays on your device. Nothing is uploaded, stored or shared, and it continues to work offline once the page has loaded.
What is the difference between resizing and compressing?
Resizing changes the pixel dimensions of the image. Compressing keeps the dimensions and reduces the file weight by re-encoding at a lower quality. If a form rejects your file for being too large, either can help, but resizing usually has the bigger effect.
How do I resize an image without stretching it?
Leave the aspect ratio lock on so width and height change together. If the shape still does not match what you need, crop the image to the right proportions first, then resize it to the exact dimensions.