What is WebP?

WebP is Google's image format designed to replace JPEG and PNG with a single, more efficient option. It combines the strengths of both: the compression efficiency and small file sizes of lossy JPEG with support for transparency like PNG, all while achieving 25–35% smaller file sizes than JPEG at the same quality level. WebP was introduced in 2010 and has steadily gained browser support, making it increasingly practical for modern web projects.

How WebP compression works

WebP offers two compression modes: lossy and lossless. In lossy mode, WebP discards some visual information to achieve dramatic file size reductions — similar to JPEG. Lossy WebP is ideal for photographs where tiny quality loss is invisible to human eyes. In lossless mode, WebP preserves all image data perfectly, comparable to PNG, though files are still smaller than PNG because WebP's compression algorithm is more modern and efficient.

For a typical high-quality photograph: a JPEG might be 200 KB, PNG might be 500 KB, and WebP lossy would be around 130–150 KB at visually identical quality. For graphics with transparency, PNG might be 100 KB and WebP lossless could be 60–70 KB. These differences compound at scale — a website serving thousands of images saves significant bandwidth and loads faster by using WebP.

WebP transparency and animation

Like PNG, WebP supports full transparency (alpha channel). This makes WebP suitable for logos, icons, and graphics that need to blend seamlessly onto any background. WebP also supports animation similar to GIF — a single WebP file can contain multiple frames with timing information, creating animated images at smaller file sizes than GIF or animated PNG.

Browser support for WebP

WebP support is widespread in modern browsers. Chrome, Edge, and Firefox support it natively. Safari added support in 2022 (iOS 16 and macOS Ventura). Internet Explorer does not support WebP — if you need to support users on older Windows machines with IE, you must provide a fallback format like JPEG or PNG. Most modern web projects use WebP as a primary format with a fallback to JPEG or PNG for older browsers.

WebP vs JPEG — quality and file size

JPEG has been the standard for photographs since 1992. Both JPEG and lossy WebP discard visual information to reduce file size, but WebP's algorithm is more sophisticated. At identical file sizes, WebP typically delivers noticeably better quality than JPEG. Conversely, at identical quality levels, WebP files are 25–35% smaller than JPEG. This advantage compounds across an entire website — a photo gallery in WebP loads significantly faster than in JPEG.

WebP vs PNG — transparency and compression

PNG excels at lossless compression and transparency, making it essential for graphics, logos, and any image where every pixel must be preserved. Lossless WebP offers similar visual results to PNG with 20–30% smaller files. However, PNG is more universally supported in legacy systems and some older software. For modern web projects, WebP with PNG fallback is the standard approach.

When to use WebP

Use WebP if: You're building a modern website and want to optimize for performance. You're serving the same image to desktop, mobile, and tablet devices — WebP's superior compression saves bandwidth everywhere. You're designing for modern browsers (Chrome, Edge, Firefox, Safari). Use JPEG if: You need maximum compatibility with older systems or if you're uploading to services that don't accept WebP. Use PNG if: You need transparency, lossless quality, or must support Internet Explorer.

Converting to and from WebP