What Internet media type is registered for WebP images?

The Internet media type registered for WebP images is image/webp.

A media type, also called a MIME type, tells software what kind of content is being transferred. When a web server sends a WebP file with Content-Type: image/webp, browsers and other clients can identify it as an image and decide how to decode or display it. The subtype “webp” follows the standard image slash subtype pattern used by formats such as image/png and image/jpeg.

WebP was developed at Google and is based on technology associated with the VP8 video codec. It supports both lossy and lossless compression, plus transparency and animation. Those capabilities let it cover some uses traditionally handled by JPEG, PNG, or GIF while often producing smaller files.

The media type is not the same thing as a file extension: “.webp” is the usual filename suffix, while image/webp is the protocol label. The tempting alternatives in this question are either unrelated, nonstandard, or refer to other image formats.