Big image files slow down websites, clog inboxes and eat storage. The trick to compressing images without losing quality is knowing how far you can push it before anyone notices, and this guide shows you exactly that, plus how to compress for free in your browser.
How image compression works
Most compression is "lossy": it throws away detail your eye barely registers to make the file dramatically smaller. Done well, an image can shrink 50-70% with no visible difference. Done too aggressively, you get blocky artifacts. The goal is finding that sweet spot, usually around 70-85% quality for photos.
How to compress an image (step by step)
- Open the Compress Image tool and upload a JPG, PNG or WebP.
- Choose an output format (WebP compresses best; JPG is most compatible).
- Drag the quality slider and watch the size estimate.
- Optionally set a max width to also scale big photos down.
- Compress and download, you'll see the before/after size.
Target sizes by use
| Use | Good target |
|---|---|
| Website hero image | Under 200 KB, ~1600px wide |
| Blog/inline image | Under 100 KB, ~1000px wide |
| Email attachment | Under 1 MB total |
| Social post | ~1080px, under 300 KB |
Tips
- Convert to WebP for websites, smaller than JPG at the same quality.
- Keep the original since lossy compression can't be undone.
- Resize first, compress second for the biggest savings.
🗜️ Ready to compress image?
Free, private and instant, right in your browser.
Open the Compress Image tool →Frequently asked questions
How do I compress an image without losing quality?
Upload it, then nudge the quality slider until the preview size looks good, around 70-80% keeps images looking sharp while cutting the file size a lot.
How much smaller will my image get?
It depends on the photo, but detailed JPGs often shrink by 40-70%. PixOtter shows you the exact before-and-after size.
Can I compress and resize at the same time?
Yes. Set a max width and PixOtter scales the image down and compresses it in one step.
Is my photo uploaded to compress it?
Never. Compression happens on your device, so nothing is sent to a server.