At a glance
| Input | Any image the browser can open |
|---|---|
| Output | The format it came in — JPG, PNG or WebP |
| Sizing | Exact width and height, or a percentage |
| Where it runs | Entirely in your browser — no file is uploaded to a server |
| Price | Free, with no account and no sign-up |
| Offline | Works with no connection after the first visit |
Pixels, percentages and the lock
Type a width and the height follows, because the lock keeps the proportions. Unlock it and you can force any shape you like, at the cost of a stretched picture — useful for a banner slot that demands exact numbers, wrong for a photograph of a person.
Percentages are easier when you know the result is "half the size" rather than a specific number, and they keep a batch of differently sized originals in proportion to each other.
Making an image bigger
Enlarging invents pixels that were never captured. The browser interpolates between the ones it has, so a 400px photo blown up to 1600px looks soft rather than detailed — no resizer can recover information the camera did not record.
Going up to about 150% is usually acceptable. Beyond that, find a larger original if you can; if you cannot, the upscaler uses a trained model rather than plain interpolation and does better on illustrations and faces.
What the file size does
Halving both dimensions leaves a quarter of the pixels, so the file usually falls by rather more than half. If you are resizing purely to save space, resize first and then run it through image compression — the two together beat either alone, and in that order the compressor is working on fewer pixels.
A PNG of a photograph is the exception: it stays large whatever you do to it, because PNG stores every pixel exactly. Convert it to JPG or WebP if it is a photograph rather than a diagram.
Frequently asked questions
Will resizing make my photo blurry?
Making it smaller will not — there is more information than the new size needs. Making it larger will, because the extra pixels are guessed from their neighbours. Up to about 150% that is hard to notice; well beyond it, it shows.
How do I hit an exact file size, not an exact width?
Resizing controls dimensions, not bytes. Resize to the dimensions you need first, then use the image compressor, which has a quality slider and shows the resulting size as you move it.
Does it keep transparency?
Yes, if you keep the format as PNG or WebP. Saving a transparent image as JPG replaces the transparent areas with solid colour, because JPG has no alpha channel.
Can I resize several at once?
Not here — this one is built around getting a single image to a precise size. For a folder of images, the compressor takes a batch and has a maximum-dimension setting that resizes as it goes.
Are my images uploaded?
No. The image is decoded and redrawn by your own browser, and the result is saved straight to your downloads. You can watch the network tab stay empty.
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