Image Format Converter - Free Online Tool

The three formats here are good at different things, and choosing correctly matters more than any setting. JPEG is lossy and built for photographs: it discards detail the eye barely registers, which makes it very efficient on continuous-tone images like landscapes and portraits, but it cannot store transparency and it re-compresses every time you save.

PNG is lossless and supports a full alpha channel. That makes it right for logos, icons, screenshots, diagrams and anything with hard edges, flat colour or transparency, all of which JPEG mangles into visible fringing around the edges. The cost is size: a photograph saved as PNG is often several times larger than the same image as JPEG, because lossless compression has far less redundancy to exploit in a noisy photographic image.

WebP handles both cases. It supports lossy and lossless modes and transparency, and typically lands 25 to 35 percent smaller than an equivalent JPEG or PNG. Support is now universal across current browsers, which makes it the sensible default for anything going on a website. The one place to be careful is compatibility with older desktop software and some print workflows, where JPEG remains the safest thing to hand over.

A useful rule of thumb: photograph for the web goes to WebP, photograph for someone else's system goes to JPEG, anything with transparency or text goes to PNG or WebP, and never route a graphic with sharp edges through JPEG. Conversions run on a canvas in your browser, batch mode handles a whole selection at once, and no file is uploaded.