How to Compress Images Without Losing Quality
Shrink photos for the web by choosing the right format and quality level, and know exactly what compression can and cannot preserve.
The honest definition of without losing quality
JPG, WebP and PNG all rewrite image data when you compress, and lossy formats discard some permanently. The practical goal is not zero change but an image that looks the same to a person at the size it will be seen. A page thumbnail survives compression that would ruin a full-screen hero image.
The three levers that matter
Resolution, format and quality setting decide most of the file size. Halving the pixel width quarters the data; a modern format saves further; quality trades fine gradients for bytes. Every lossy resave also compounds: a JPG saved ten times carries ten rounds of discarded detail, visible as blotchy patches and ringing along hard edges.
- Open the Compress image tool and choose your photo.
- Pick the format: WebP usually smallest, JPG the universal fallback, PNG for flat graphics.
- Lower the quality setting stepwise, checking the preview after each step.
- Stop at the first setting where you cannot see a difference at display size.
- Save and compare the new file size against the original.
Match the format to the image type
Photographs compress well in WebP and JPG, built for smooth gradients and texture. Flat colors, logos, text and screenshots often do better as PNG, whose lossless mode preserves hard edges exactly even at a larger file size. A photograph rarely benefits from PNG, and a logo in a lossy format can grow fuzz around the letters.
Review and troubleshooting
Compare compressed and original side by side at final display size before deleting anything. If banding appears in skies or skin, raise quality one step. If the file is still heavy, reduce resolution rather than crushing quality. Keep one untouched original in an archive folder, so every future export starts from clean data.
Common questions
Is any compression truly lossless?
Yes. PNG's lossless mode rebuilds the exact original pixels. It shrinks less, but nothing is discarded, which is why it suits logos and screenshots.
Why does my photo get worse each re-save?
Each lossy save repeats the discarding step on already-damaged data, so artifacts accumulate. Export each time from the one original you keep.
Try the workflow
Prepare your own file and review the result before using it.
Open the related Clipy tool