Just Tool It
Just Tool It / Image Compress
On-device — nothing uploaded

Compress JPG & PNG

Drop an image, slide the quality knob, and download a smaller file. Side-by-side size comparison.

Drop one or more images here

or browse from your device — JPG, PNG, WebP supported. Drop multiple to batch-compress and get a .zip back.

Why compress images in your browser?

Image compressors are everywhere, but most of them upload your file to a remote server, process it there, and send it back. That round trip is slow and exposes the picture to a third party. Just Tool It re-encodes the image inside your browser using the built-in Canvas and image decoders that ship with Chrome, Safari and Firefox. The original file stays on your device.

How to compress an image (step-by-step)

  1. Drop an image onto the upload area, or click to browse.
  2. Choose a quality. 75–85% looks identical to most viewers for typical photos.
  3. Optionally cap the dimensions. Most uses don't need anything wider than 1920 px.
  4. Click Compress to re-encode. The result card shows the new size.
  5. Click Download to save it.

Frequently asked questions

Does compressing reduce image quality?
JPEG and WebP are lossy formats — lower quality settings produce smaller files at the cost of some sharpness. Use the slider to find a setting where the difference is barely visible. PNG is lossless, so its savings come mostly from dimension caps.
Are my images uploaded anywhere?
No. The image is decoded with your browser's image engine, redrawn onto a canvas, and re-encoded with canvas.toBlob. Nothing is sent to a server.
Why is my PNG sometimes bigger after compression?
PNG is lossless: the browser's PNG encoder has limited options compared to dedicated tools, so re-encoding a small PNG can occasionally produce a slightly larger file. If you can accept some quality loss, switch the output to JPEG or WebP — both are usually dramatically smaller.