压缩 WebP

WebP was designed to replace both JPG and PNG on the web, and for photographs it usually needs 25–35% fewer bytes than JPG at the same visual quality. Our measurements: a 1200 × 800 JPG of 224,092 bytes became a 93,112-byte WebP at quality 80, against 132,872 bytes for the JPG at the same setting. The same photo stored as a 1,601,750-byte PNG came out at 91,364 bytes as WebP, under 6% of the original.

Screenshots and graphics gain too, and unlike JPG, WebP keeps transparent areas transparent, so a logo can move from PNG to WebP without picking up a white box.

A WebP you already have, saved from a website or exported by a CMS, is decoded and encoded again at the quality you set. Files saved at a high quality shrink noticeably: a 1200 × 800 WebP we exported at quality 95, 229,732 bytes, came down to 94,064 bytes. Files that a site already squeezed hard may not get smaller; in that case you get the original back unchanged rather than a larger copy. Lowering the maximum dimensions is the more reliable way to shrink those.

Animated WebP files lose their animation here: only the first frame is decoded and saved. Keep the original for animations.

Every current browser displays WebP, including Safari since version 14, and WordPress, Shopify and most site builders accept it. It is a good choice for images on your own site, where smaller files load faster. It is a poor choice for files you send to people: some email clients, older Windows photo viewers, print shops and many government or job portals still only take JPG or PNG.

Encoding is done by your browser. Chrome, Edge and Firefox can write WebP; Safari cannot encode it from a canvas and falls back to PNG, so there you get that PNG or your original, whichever is smaller, but no WebP. Use one of the other browsers to create WebP files.

Decoding and encoding happen in the browser tab, and the images never leave your computer. Up to 10 files fit in a batch at 50 MB each, Download all builds a ZIP, and the bulk compressor raises the batch to 50 files. EXIF data is removed unless you turn on Preserve EXIF.