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.
Compress Images Without Uploading Them
Compression is applied in the browser with the canvas API, so the originals are never transmitted. That matters for screenshots of private dashboards, photographed paperwork and anything else you are shrinking to attach to an email.
No signup and no daily image quota. Large photos straight off a camera are limited only by your device's memory rather than an upload ceiling.
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.
Is there a file size limit or a daily quota?
No. Nothing is uploaded, so there is no bandwidth cost to meter and no free-tier cap. Very large images are bounded only by your browser's memory.
Do I need to sign up to compress images?
No. No account, no email, and no watermark on the compressed image.