[null,null,["最后更新时间 (UTC)：2025-08-08。"],[[["\u003cp\u003eWebP is a modern image format that offers superior lossless and lossy compression for images on the web, resulting in smaller and richer images.\u003c/p\u003e\n"],["\u003cp\u003eWebP lossless images are 26% smaller than PNGs and lossy images are 25-34% smaller than comparable JPEGs at equivalent quality.\u003c/p\u003e\n"],["\u003cp\u003eWebP supports transparency in both lossless and lossy modes, providing significant size reductions compared to PNGs.\u003c/p\u003e\n"],["\u003cp\u003eAnimated WebP images offer reduced file sizes compared to GIFs and APNGs while supporting lossy, lossless, and transparency.\u003c/p\u003e\n"],["\u003cp\u003eWebP is natively supported in major web browsers like Chrome, Safari, Firefox, Edge, and Opera, as well as many other tools and software libraries.\u003c/p\u003e\n"]]],["WebP, a modern image format, offers superior lossless and lossy compression compared to PNGs and JPEGs. Lossless WebP images are 26% smaller than PNGs, and lossy WebP images are 25-34% smaller than JPEGs. WebP supports transparency, even in lossy formats, and animated WebP images. It employs predictive coding for lossy compression and utilizes existing image fragments for lossless compression. Supported by major browsers and tools, WebP includes the `libwebp` library and `cwebp`/`dwebp` conversion tools.\n"],null,["# An image format for the Web\n\nWebP is a modern **image format** that provides superior **lossless and\nlossy** compression for images on the web. Using WebP, webmasters and web\ndevelopers can create smaller, richer images that make the web faster.\n\nWebP lossless images are [26% smaller](/speed/webp/docs/webp_lossless_alpha_study#results) in size compared to PNGs. WebP\nlossy images are [25-34% smaller](/speed/webp/docs/webp_study) than comparable JPEG images at equivalent\n[SSIM](https://en.wikipedia.org/wiki/Structural_similarity) quality index.\n\nLossless WebP **supports transparency** (also known as alpha channel) at a\ncost of just [22% additional bytes](/speed/webp/docs/webp_lossless_alpha_study#results). For cases when lossy RGB compression\nis acceptable, **lossy WebP also supports transparency**, typically providing\n3× smaller file sizes compared to PNG.\n\nLossy, lossless and transparency are all supported in **animated WebP images**,\nwhich can provide reduced sizes compared to GIF and APNG.\n\n- **[More Info for Webmasters](/speed/webp/faq#how_can_i_detect_browser_support_for_webp)**\n\nHow WebP Works\n--------------\n\nLossy WebP compression uses predictive coding to encode an image, the same\nmethod used by the VP8 video codec to compress keyframes in videos. Predictive\ncoding uses the values in neighboring blocks of pixels to predict the values\nin a block, and then encodes only the difference.\n\nLossless WebP compression uses already seen image fragments in order to\nexactly reconstruct new pixels. It can also use a local palette if no\ninteresting match is found.\n\n- **[WebP Compression Techniques in Detail](/speed/webp/docs/compression)**\n\nA WebP file consists of [VP8](https://datatracker.ietf.org/doc/rfc6386/) or [VP8L](/speed/webp/docs/webp_lossless_bitstream_specification) image data, and a container\nbased on [RIFF](/speed/webp/docs/riff_container). The standalone `libwebp` library serves as a reference\nimplementation for the WebP specification, and is available from\n[our git repository](https://www.webmproject.org/code/#libwebp-webp-image-library) or as a [tarball](/speed/webp/download).\n\nWebP Support\n------------\n\nWebP is natively supported in Google Chrome, Safari, Firefox, Edge, the Opera\nbrowser, and by [many other](/speed/webp/faq#which_web_browsers_natively_support_webp) tools and software libraries. Developers have\nalso added support to a variety of image editing tools.\n\nWebP includes the lightweight encoding and decoding library [`libwebp`](/speed/webp/docs/api)\nand the command line tools [`cwebp`](/speed/webp/docs/cwebp) and [`dwebp`](/speed/webp/docs/dwebp) for converting\nimages to and from the WebP format, as well as tools for viewing, muxing and\nanimating WebP images. The full source code is available on the\n[download](/speed/webp/download) page.\n\nWebP Converter Download\n-----------------------\n\nConvert your favorite collection from PNG and JPEG to WebP by downloading the\nprecompiled `cwebp` conversion tool for [Linux, Windows or macOS](/speed/webp/docs/precompiled).\n\nTell us your experience on the project's [mailing list](https://groups.google.com/a/webmproject.org/group/webp-discuss)."]]
