Oversized images slow down websites, get rejected by upload forms and eat your mobile data. The good news: with the right format and quality setting, you can usually cut image size by 70–90% with no visible difference. Here is everything you need to know.
First, Understand the Two Types of Compression
- Lossy compression: permanently discards details your eyes barely notice. File size drops dramatically. JPG and lossy WebP work this way — ideal for photos.
- Lossless compression: optimizes storage without touching a single pixel. PNG works this way — perfect for icons, screenshots and anything needing transparency, but the size reduction is modest.
Rule of thumb: photos → lossy (JPG/WebP); icons and screenshots → lossless (PNG). Choose the wrong direction and no slider setting will save you.
Picking the Right Format Does Half the Work
| Format | Compression | Transparency | Best for |
|---|---|---|---|
| JPG | High (lossy) | No | Photos, banners, product images |
| PNG | Low (lossless) | Yes | Icons, logos, screenshots |
| WebP | Highest (both) | Yes | Web images, smallest files |
At the same visual quality, WebP is 25–35% smaller than JPG. For anything published on a website, WebP is almost always the right answer; fall back to JPG only for compatibility with very old software.
The Quality Sweet Spot: 60–80
- 60–70: smallest files — chat apps, forum uploads.
- 75–80: best balance — blog images, product photos.
- 85–90: quality first — portfolios, print materials.
- 90+: almost no extra visible quality, rarely worth it.
Quality degradation is non-linear: 100 → 80 is invisible to most eyes, while 80 → 50 looks visibly blurry. Always start at 80 and work downwards.
Recommended Settings by Scenario
| Scenario | Format | Quality | Target size |
|---|---|---|---|
| Email attachments | JPG | 70–80 | < 1 MB each |
| Blog / website images | WebP | 75–80 | 100–300 KB each |
| E-commerce product photos | JPG | 80–85 | < 500 KB each |
| Social media posts | JPG | 75–85 | < 1 MB each |
Compress an Image in 30 Seconds
- Open the Image Compressor and drop your file in
- Drag the quality slider (start at 75%) and watch the live size preview
- Switch the output to WebP for an extra size cut, then download
Recommended Tools
Image Compressor
Compress JPG, PNG and WebP images online by up to 90% with almost no visible quality loss.
Format Converter
Convert images between PNG, JPG and WebP in one click while keeping quality.
Free online, images never leave your browser
FAQ
My compressed photo looks terrible — what now?
Raise the quality back to ~85, or switch the output format to WebP: at the same file size, WebP keeps noticeably better quality than JPG.
Why won't my PNG get much smaller?
PNG is already losslessly optimized. If the image is a photo, re-saving it as JPG or WebP typically cuts the size by more than 50%.
Is it safe to compress images online?
It is here. Every tool on this site runs entirely in your browser — your images are never uploaded to any server.