Compress images in the browser

Photographs are often larger than the screen they will be shown on. A 4000-pixel-wide camera file is wasted if the layout only displays it at 1200 pixels. Compression has two separate levers: the pixel dimensions, and the quality of the format you save. Changing either one can shrink the file. Changing both usually shrinks it more.

JPEG and WEBP can discard detail that is hard to see. The quality slider on the compressor controls that trade. Around 0.75, many photos look the same at a glance and take much less space. Going much lower starts to show blocks, especially in skies and flat walls. PNG does not use that quality value in the same way, because PNG is built to keep every pixel. If you need a smaller PNG of a photograph, switch the output to JPEG or WEBP, or reduce the width and height.

Screenshots and logos behave differently from photos. Large areas of one colour compress well, and a modest resize often matters more than the quality slider. If the image has transparency, JPEG will flatten it. Keep PNG or WEBP when the transparent background is part of the design.

Because the work happens in the tab, the limit is your device’s memory, not an upload cap. Very large files can still make the tab slow. Resize first if the browser struggles, then adjust quality while you compare the before and after sizes shown next to the previews.

Keep the original file. Compression for the web is a copy, not an archive. The tool does not add a watermark and does not require an account. Related tools on this site can resize, convert the format, or crop before you compress.