Image Compressor
Reduce image file size. Free, no signup, no upload.
How It Works
Select an image and adjust the quality slider. Click Compress to re-encode the image as a JPG at the specified quality level. You will see the original and compressed file sizes. No file is ever uploaded to a server.
Why Compress Images?
Compressed images load faster on websites, take less storage space, fit under email attachment limits, and meet upload size requirements. Reducing quality from 100% to 80% typically cuts file size by 50% or more with barely visible difference.
Choosing a Quality Level
The slider ranges from 5% to 100%. Higher values keep more detail and larger files; lower values save more space but can introduce visible blocky artefacts. These are good starting points:
| Quality | Result | Good for |
|---|---|---|
| 90-100% | Near-original detail, modest savings | Photos you will print or edit |
| 75-85% | Big size drop, hard to tell apart | Websites, blogs, general sharing |
| 50-70% | Noticeable but acceptable loss | Thumbnails, email, tight size limits |
| Below 50% | Visible artefacts, smallest files | Only when size matters most |
Because the output is JPG, a transparent PNG will come out with a white background. If you need to keep transparency, resize the PNG instead of compressing it here.
Frequently Asked Questions
How do I compress an image online?
Select an image, drag the quality slider to the level you want, and click Compress. The tool re-encodes the picture as a JPG, shows the original and compressed sizes, and gives you a Download button for the smaller file.
How much smaller will my image get?
It depends on the image and the quality you choose, but lowering quality from 100% to around 80% often cuts file size by half or more with little visible difference. The tool shows the exact before-and-after size and the percentage saved after each compression.
What format is the compressed image?
The output is always a JPG, saved as your-file-compressed.jpg, regardless of the input format. JPG is what makes the strong size reduction possible. Note that transparent areas of a PNG are filled with a white background because JPG does not support transparency.
Does compressing change the image dimensions?
No. The width and height are kept exactly as in the original; only the encoding quality changes. If you also need to change the pixel dimensions, use the Image Resizer.
Are my images uploaded to a server?
No. Compression runs entirely in your browser using an HTML canvas, so your images never leave your device and nothing is uploaded, stored, or sent anywhere.