Resize an Image Without Losing Quality
Make it smaller, do it once, and compress last. The four ways a resize quietly costs you quality, and how to avoid each.
To resize an image without losing quality, make it smaller rather than bigger, resize once from the original file, and compress only at the very end. Shrinking throws away pixels you weren't going to see anyway. Enlarging asks the software to fill in pixels that were never captured, and no tool can do that truthfully. The rest of this guide covers the smaller ways quality slips out during a resize, and how to avoid each one.
Which resizes lose quality?
Not every resize costs the same. This is where the damage comes from:
| What you do | What happens to quality | What to do instead |
|---|---|---|
| Shrink (4000px wide down to 1200px) | Each new pixel is blended from several originals. Detail finer than the new size goes, but the result looks clean. | Nothing. This is the safe direction. |
| Enlarge | New pixels are estimated from their neighbours, so edges blur and any compression blocks in the small file get magnified. | Find a larger original. |
| Change width and height independently | The picture stretches. Faces widen and circles turn oval. | Keep the aspect ratio locked and crop to change the shape. |
| Resize a copy that was already resized | Every pass resamples again, so the softening adds up. | Always go back to the original. |
| Save as JPG between steps | Each lossy save adds its own artefacts on top. | Compress once, as the last step. |
Why can't enlarging add detail?
Because the detail was never stored in the file. A 400-pixel-wide photo holds 400 columns of real information. Ask for 1600 and the software has to invent three new columns for every real one, which it does by averaging the pixels around each gap. The result is bigger, not sharper. That blur, plus any magnified compression blocks, is what people usually mean by "pixelated" when a small picture is stretched to fill a screen.
babapic has no upscaler. Resize by Percentage accepts values up to 500%, and Resize Image will take a width larger than your photo, but both only stretch what is there. AI upscalers on other sites paint in plausible-looking texture, which is a prediction rather than your photo's real detail. If you need a large image, the original camera file or the highest-resolution copy you can find will beat any enlargement.
How to resize an image without losing quality
- Start from the original. Use the file from your camera or phone, not a copy saved from a chat app or social site, which has often been shrunk and recompressed already.
- Open Resize Image and drop the file in. It runs in your browser; the photo is never uploaded.
- Type the width you need. With Lock aspect ratio ticked (the default), the height fills itself in. Leave it that way.
- Check you're going down. The readout shows the new size next to the original's. If the new number is bigger, you're enlarging.
- Resize and download. Drop in several photos and each one comes out at that width with its own height, bundled in one zip.
What the resize does to your file
The tool redraws your image at the new size and saves it in the format it came in, under the same file name. A PNG stays a lossless PNG; a JPG or WebP is saved again at quality 0.92. That is a high setting, but it is still one lossy save, and a transparent PNG stays transparent.
Lossy saves add up, which is what generation loss describes: each one compounds the last. So if the resized JPG still needs to be smaller (for an upload limit, say), run it through Compress Image once and stop there. That route costs two lossy saves, one of them at high quality.
To get it down to one, work in PNG until the end. Convert the original with JPG to PNG, then crop and resize the PNG, which both stay lossless, and save it as a JPG once with PNG to JPG at the quality you choose. For how the two kinds of compression differ, see lossy vs lossless compression.
Can you shrink too far?
Yes. If you resize below the size an image is shown at, the app or web page stretches it back up, and you're enlarging again without meaning to. Pick a width at or above where it'll be displayed. Our guide on how to resize an image lists sensible sizes for the web, email, and forms, and what image resolution means covers how many pixels a print or screen needs.
Cropping is the other way to lose resolution by accident. Every pixel you crop away is gone, so crop first, check the remaining size, and only then shrink.
FAQ
Does resizing an image reduce its quality?
Shrinking keeps the picture clean, because the detail it drops is detail the smaller size couldn't show. Enlarging always softens it.
How do I make a small photo bigger without it going pixelated?
You can't recover detail the file never held. Resize Image smooths the new pixels rather than drawing hard blocks, but the bigger the jump, the softer the result. Look for a bigger original first.
Does resizing a JPG add compression?
A little. The resized file is saved again as a JPG at quality 0.92. To avoid that extra save, convert to PNG first, resize, and convert back to JPG once at the end.
Can I resize a batch of photos without stretching any?
Yes. Leave Lock aspect ratio on and set only the width: each photo gets that width and keeps its own proportions.