How to compress an image
- Pick an image — compression runs instantly in your browser.
- Drag the quality slider; watch the live file-size savings.
- Download when the balance looks right.
What quality should I use?
- 75–85% — the sweet spot: big savings, no visible loss.
- 60–75% — great for web pages and email.
- Below 50% — smallest files, visible artifacts.
Why compress images?
Smaller images make pages load faster — better user experience, better SEO, less bandwidth. A photo straight off a phone is often 3–8 MB; compressed for web it can be 200–500 KB with no visible difference.
Benefits
- Shrinks file size with a live quality slider so you can see the trade-off as you go.
- Runs in your browser — images are never uploaded.
- Great for getting under email attachment limits and speeding up web pages.
- Free and unlimited.
Limitations to know
- Compression is lossy, so pushing quality too low introduces visible artifacts.
- An image that is already optimized will not shrink much further.
- PNGs with transparency compress less than photos saved as JPG.
Common mistakes to avoid
- Dragging the quality slider so low that the image looks blocky.
- Compressing before resizing — resize to the final size first, then compress.
- Keeping a photo as PNG when JPG or WebP would be far smaller.
- Expecting large savings on files that are already small.
Alternatives
To change the pixel dimensions instead, use the Image Resizer. Converting a photo to WebP with the Image Converter often produces a smaller file at the same quality.
Last updated: August 2026 · Reviewed by the AI Toolbox editorial team.
Frequently asked questions
Is my image uploaded?
No — compression runs entirely on your device. Nothing is sent to any server.
Does it work with PNG?
Yes — PNGs are re-encoded as high-quality JPEG for maximum savings (transparency becomes white). To keep transparency, use the Image Converter to WebP.