Compress images without visible loss
Drop in one or more images, set the quality slider (75% works for most photos) and, if you want, a maximum size. The tool shows the file size before and after, and the percentage saved. Your images never leave your device: everything is compressed inside your browser.
- ✅ Free
- 🔒 No sign-up
- 📱 Works on mobile
- ⚡ Instant results
🔒 Everything runs in your browser. Your data and files never leave your device.
How the tool shrinks an image
Your image is redrawn on a browser canvas, then re-encoded in the format you pick at the quality you set. Two things bring the file size down:
- Quality (JPEG and WebP): the lower it goes, the smaller the file, at the cost of fine detail. Between 70% and 85% the difference is rarely visible.
- Dimensions: a 1,920 px side is plenty for a screen, and 1,280 px for a website or a message. Fewer pixels means a proportionally smaller file.
\[ \text{savings (\%)} = \dfrac{\text{size before} - \text{size after}}{\text{size before}} \times 100 \]
If the result would be larger than the original (an image that is already heavily compressed), the tool keeps the original instead of making it bigger.
JPEG, PNG or WebP: which format?
| Format | Compression | Transparency | Best for |
|---|---|---|---|
| JPEG | lossy | no | photos |
| PNG | lossless | yes | logos, screenshots, diagrams |
| WebP | lossy or lossless | yes | websites: roughly 25% to 35% smaller than a comparable JPEG |
PNG ignores the quality slider. To make one smaller, switch to WebP (transparency is kept) or reduce its dimensions. When a transparent PNG is converted to JPEG, the transparent areas turn white.
What file size should you aim for?
| Use | Max side | Quality | Target size |
|---|---|---|---|
| Email attachment | 1,920 px | 75% | under 500 KB per photo |
| Blog post image | 1,280 px | 75% | under 200 KB |
| Full-width website photo | 1,920 to 2,560 px | 80% | under 400 KB |
| Thumbnail | 400 to 800 px | 70% | under 60 KB |
These are rules of thumb. The exact size depends on the picture: a plain sky compresses far better than leafy trees.
3 real-life examples
A 4.2 MB smartphone photo
A 4,032 × 3,024 px photo weighs 4.2 MB. You set the maximum side to 1,920 px (it becomes 1,920 × 1,440 px) and the quality to 75%. The result lands around 350 to 450 KB, about 90% saved, with no visible difference on a screen.
10 photos for an email
Ten 3.5 MB photos add up to 35 MB, over Gmail's 25 MB attachment limit. After compressing to 1,920 px at 75%, each photo is around 450 KB and the batch is 4.5 MB. You download it as a single zip.
A 1.8 MB PNG screenshot
Switch the output format to WebP at 85%. The screenshot drops to around 250 KB, close to 86% saved, and text stays sharp.