What is WebP? The Modern Web Image Format Explained
If you have run a speed test on PageSpeed Insights recently, you have likely seen a recommendation to "Serve images in next-gen formats." The primary format behind this recommendation is WebP.
In this article, we'll explain what WebP is, its advantages, and why you should migrate to it today.
What is WebP?
WebP is a modern image format developed by Google in 2010. Its goal is simple: to create smaller, richer images that make the web faster. WebP can compress files significantly better than JPEG or PNG while retaining high visual fidelity.
Core Advantages of WebP
WebP is a hybrid format that combines the best features of PNG, JPEG, and GIF:
- Lossy Compression: Like JPEG, WebP can compress photos with lossy algorithms. However, WebP lossy images are 25% to 34% smaller than comparable JPEGs.
- Lossless Compression: Like PNG, WebP supports lossless compression. Lossless WebP images are 26% smaller than PNGs.
- Transparency: WebP supports alpha channel transparency in both lossy and lossless modes, something JPEG cannot do.
- Animation: WebP supports animated images, making it a modern replacement for bloated GIF files.
How Does WebP Achieve Smaller Sizes?
WebP uses a technique called predictive coding (borrowed from the VP8 video codec) to compress images. It looks at neighboring blocks of pixels to predict the values in a block, and then only encodes the difference. This makes compression incredibly efficient.
Compatibility
All modern web browsers, including Chrome, Safari, Firefox, Edge, and Opera, fully support WebP. For older legacy browsers, you can set up a fallback using the HTML <picture> tag.