How to use Image Compressor

The short answer

To compress an image, drop a JPG, PNG or WebP file, then pick a quality or a target size such as 100 KB. ClickZM re-encodes it in your browser, shows the before and after size, and lets you download the smaller file; batches of up to 50 images are supported.

It runs in your browser. What you enter is not uploaded.

How to use it

Choose your file with the upload box above, or drag and drop it onto the box.

Adjust the options; the preview updates as you change them.

Click the main button to process the file in your browser.

Download the result. Your original file is never changed or uploaded.

How the result is worked out

Images are decoded and re-encoded in your browser at the quality you choose. With a target size, the tool searches for the highest quality that fits and reduces the dimensions only if quality alone is not enough. A PNG with a size target is saved as JPEG, because PNG has no quality setting.

Every re-save of a JPEG loses a little detail, so compress from the original rather than an already compressed copy. Around quality 75 the difference is usually invisible on screen; screenshots with text look sharper as WebP.

Limits worth knowing

How much smaller will my photo get? Phone photos usually shrink 60–85% at quality 75 with no visible difference. PNG screenshots shrink most when converted to WebP.

Can I compress to an exact size like 50 KB? Yes. Enter a target in KB: the tool searches quality settings and, if needed, reduces dimensions until the file fits.