Shrink an image for the web and see exactly what you are trading away. The original and the compressed version sit side by side, with the file size saving shown underneath.

Your image is never uploaded. Compression happens on your device using the browser's canvas, which is why it works offline and why nothing appears in any server log.

How to use this tool

Drop an image in, or choose a file.
Pick an output format and quality level.
Compare the before and after previews.
Download when you are happy.

Choosing a format

WebP — typically 25–35% smaller than JPEG at equivalent quality, and supported by every current browser. This is the right default for the web.
JPEG — universal support, including old software and some print workflows. No transparency.
PNG — lossless, so quality is untouched and the quality slider does nothing. Keeps transparency. Use it for logos, screenshots of text, and anything with sharp edges.

Choosing a quality level

85–95% — visually indistinguishable from the original for most photos
70–85% — the sweet spot for web images; small artefacts only visible on close inspection
50–70% — clearly compressed, but fine for thumbnails and backgrounds
Below 50% — visible blockiness

Photographs compress well. Screenshots, line art, and images containing text do not — lossy compression smears text edges. Use PNG or WebP at high quality for those.

Tips

Set a max width as well. Serving a 4000px photo into a 800px slot wastes far more bytes than any quality setting will save.
If the output comes out larger than the input, the source was already compressed. Lower the quality or switch to WebP.
Compress once, from the original. Repeatedly re-compressing an already lossy image compounds the artefacts.

Related tools

Image format converter — batch convert without resizing
Image resizer — change dimensions precisely
Favicon generator — build a full icon set from one logo
Image to PDF — collect images into a document

FAQ

Is my image uploaded to a server?

No. The file is read into a canvas element in your browser and re-encoded there. There is no upload, no queue, and no copy on any server.

Does it work offline?

Yes, once the page has loaded. That is a direct consequence of the processing being local.

Why is my PNG barely getting smaller?

PNG is lossless, so the quality slider is disabled and the only saving comes from re-encoding. To make a PNG substantially smaller, convert it to WebP — which supports transparency too.

Does compressing remove EXIF data?

Yes. Re-encoding through a canvas drops EXIF metadata, including GPS coordinates. That is usually a privacy win when publishing photos.

What is the maximum file size?

There is no fixed limit, but very large images (above roughly 30 megapixels) can exhaust the tab's memory on lower-end devices. Resize first if you hit trouble.

Image Compressor