Image Compressor

What this tool is for

Large images are the most common reason a page loads slowly, and the fix is usually quality 75 rather than a redesign. Drop in one file or twenty, move the slider, and watch the saving in kilobytes as you go. Your images are processed by your own browser through the Canvas API. They are never uploaded, which means no queue, no size limit imposed by a server, and no copy of your photo sitting in someone else storage.

How to use it

1. Drop your images onto the page, or pick them from disk.
2. Move the quality slider and watch the new file size update.
3. Optionally cap the largest dimension to stop a 4000 pixel photo being served into a 800 pixel slot.
4. Download the files individually or all at once.

Frequently asked questions

What quality setting should I use?

Between 70 and 80 for photographs. Below 60 the artefacts around edges become visible, and above 85 the file grows fast for a difference nobody sees.

Why did my PNG barely shrink?

PNG is lossless, so quality does not apply. For a photograph, converting to WebP or JPG saves far more. Keep PNG for screenshots, logos and anything with transparency or sharp text.

Is there a file size limit?

Only your device memory. Nothing is uploaded, so the usual few-megabytes cap of online compressors does not apply here.