Free Image Compressor
Shrink JPG, PNG, and WebP images without a noticeable drop in quality. Everything runs in your browser — your image is never uploaded.
Drop an image here, or
JPG, PNG, WebP, GIF or BMP — processed entirely in your browserWhat is an image compressor?
An image compressor is a tool that reduces the file size of an image while keeping it looking good. It re-encodes the picture more efficiently — and, with a lossy format, drops detail the eye barely notices — so the file downloads faster.
This compressor works entirely in your browser using the HTML canvas. Your image is never uploaded, stored, or sent anywhere — the compression happens on your own device.
How to compress an image
Add your image
Drag a JPG, PNG, or WebP file onto the box, or click to choose one.
Tune quality, format, and size
Lower the quality, pick WebP for the smallest file, and cap the width if the image is larger than it needs to be.
Download
Press Download to save the compressed image to your device.
What this tool offers
Drag and drop
Drop a file straight onto the page, or pick one manually.
Quality slider
Trade size against detail and watch the preview update.
Three output formats
Export to WebP, JPEG, or lossless PNG.
Resize on export
Cap the width to 1920, 1280, 800, or 640 pixels.
Live size comparison
See the original size, the new size, and percent saved.
100% in your browser
Your image never leaves your device — fully private.
Why does image size matter?
Image size matters because images are usually the heaviest part of a web page. A single uncompressed photo can outweigh all the text, code, and styling on the page combined — and every extra kilobyte adds load time.
Slow pages cost you visitors. Page speed is part of Google's Core Web Vitals, so heavy images can hold back your search ranking as well as frustrate people on mobile data. Compressing images is one of the simplest, highest-impact speed fixes available.
JPEG vs. PNG vs. WebP
Which format to choose for the smallest, best-looking result.
| Format | Compression | Transparency | Best for |
|---|---|---|---|
| JPEG | Lossy | No | Photographs |
| PNG | Lossless | Yes | Logos, graphics, sharp edges |
| WebP | Lossy or lossless | Yes | Almost everything — smallest files on the web |
Image optimization best practices
Do
- Export web images as WebP where possible.
- Resize an image to the size it is actually displayed.
- Aim for photos under roughly 200 KB.
- Check the preview before downloading.
- Keep an untouched original as your master copy.
Don't
- Upload camera-resolution photos straight to a website.
- Push the quality so low that the image looks blocky.
- Use PNG for photographs — the files are huge.
- Compress the same image repeatedly — quality only drops.
- Rely on the browser to resize a large image for you.
Frequently asked questions
Is this image compressor safe and private?
Yes. Your image is processed entirely in your browser using the HTML canvas. It is never uploaded to a server, stored, or sent anywhere — the file stays on your own device the whole time.
How much smaller will my image get?
It depends on the image and settings, but exporting to WebP at around 75% quality often cuts a photo's size by 50 to 80 percent. Capping the width shrinks it further. The tool shows the exact saving for your file.
Does compressing reduce image quality?
Lossy formats like JPEG and WebP drop some detail to save space, but at moderate quality the change is hard to see. Use the quality slider and the live preview to find the point where the file is small and still looks good.
Which format should I choose?
WebP for almost everything — it produces the smallest files and supports transparency. Use JPEG for wide compatibility, or PNG when you need lossless quality or transparency preserved exactly.
Why can I only export three formats?
A browser can only encode images to JPEG, PNG, and WebP through the HTML canvas. Formats like AVIF, GIF, or TIFF cannot be created in the browser, so a private in-browser tool is limited to these three.
Is there a file size limit?
There is no server limit because nothing is uploaded. The only limit is your device's memory, so extremely large images may process slowly on an older phone or computer.
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