What Is WebP? The Modern Image Format Explained and Why It Matters

WebP is an image format developed by Google that produces files 25-34% smaller than JPEG at equivalent visual quality. It supports lossy compression, lossless compression, transparency, and animation — all in one format. As of 2026, over 97% of web browsers support it, making it the de facto standard for modern web images.

How WebP Came to Exist

Google announced WebP on September 30, 2010, positioning it as a modern replacement for JPEG on the web. The format was born from a video codec: Google had acquired a company called On2 Technologies, which developed the VP8 video format. Google's engineers realized that VP8's compression techniques — designed to shrink video frames — could also produce remarkably small still images.

The early years were slow. Google shipped WebP support in Chrome almost immediately, but other browser vendors were skeptical. Mozilla publicly questioned whether the quality gains justified adopting yet another format. Apple ignored it entirely.

The turning point came gradually:

• 2012 — Chrome adds full WebP support (lossy + lossless)
• 2014 — Opera and Android Browser adopt WebP
• 2019 — Firefox finally adds WebP support (version 65, January 2019)
• 2020 — Apple adds WebP support to Safari with iOS 14 and macOS Big Sur
• 2022 — Internet Explorer retired; all surviving browsers now support WebP

That Safari holdout from 2010 to 2020 was the single biggest obstacle to WebP adoption. Once Apple relented, the format reached near-universal browser support within two years.

How WebP Compression Works

WebP offers two compression modes, each suited to different types of images:

Lossy Mode (for Photos)

Lossy WebP uses predictive coding based on VP8 — the encoder analyzes each block of pixels, predicts what it should look like based on surrounding blocks, and then stores only the difference. This technique is particularly effective for photographs with smooth gradients and organic textures.

The result: lossy WebP files are 25-34% smaller than JPEG at equivalent visual quality, according to Google's own comparative study. In practical terms, a 500 KB JPEG typically becomes a 330-375 KB WebP with no perceptible quality difference.

Lossless Mode (for Graphics)

Lossless WebP uses a different set of techniques: spatial prediction of pixels, color space transforms, palette-based coding, and entropy coding. The output is mathematically identical to the input — no data is lost.

Lossless WebP files are approximately 26% smaller than PNG files. For screenshots, logos, UI elements, and any image with sharp edges and flat colors, this is a meaningful saving with zero quality compromise.

WebP vs. JPEG vs. PNG: Side-by-Side

The practical takeaway: WebP can do everything JPEG does (better) and everything PNG does (smaller), plus animation. Its only limitation is a maximum resolution of 16,383 x 16,383 pixels — more than enough for web use, but a constraint for very large print-resolution files.

Why Modern Websites Use WebP

Web performance directly affects user experience and search rankings. Google's own Core Web Vitals metrics reward pages that load quickly, and images are typically the heaviest elements on any page. Switching from JPEG to WebP reduces image payload by roughly a third — that translates to faster Largest Contentful Paint (LCP) scores and lower bandwidth costs.

The adoption numbers reflect this. According to HTTP Archive data, WebP is now one of the most widely served image formats on the web, with adoption having grown consistently since Safari added support in 2020. Content management systems like WordPress have built-in WebP conversion since version 5.8. CDN providers including Cloudflare, Fastly, and Akamai offer automatic WebP conversion as a standard feature.

For individual site owners and developers, the conversion is straightforward. You can convert JPG to WebP or convert PNG to WebP directly in your browser using Vizua — no server upload, no software installation required.

When Not to Use WebP

WebP is excellent for web delivery, but it is not the right choice for every scenario:

• Archival storage — TIFF or PNG remain safer for long-term archival because they are lossless and supported by every imaging tool ever made.
• Print workflows — print shops expect TIFF or high-quality JPEG. Most print software does not accept WebP.
• Email attachments — JPEG is still the safest format for email, since many email clients do not render WebP inline.
• Images above 16,383 pixels — WebP's maximum dimension is 16,383 x 16,383. For panoramic or very high-resolution images, JPEG or PNG are required.

If your images end up on the web, WebP is almost certainly the right format. If they end up in print, email, or archival systems, stick with the established formats. You can always keep a WebP version for web and a JPEG version for everything else.

Need to go the other direction? Vizua also handles WebP to JPG conversion and WebP compression for files that are already in the format.

WebP and the Future: AVIF Enters the Picture

AVIF is a newer format based on the AV1 video codec that promises even better compression than WebP — roughly 20% smaller files at equivalent quality. Browser support for AVIF has grown quickly, reaching around 95% as of early 2026.

Does AVIF make WebP obsolete? Not yet. AVIF encoding is significantly slower, and the tooling ecosystem is less mature. The current best practice for performance-focused websites is to serve AVIF when the browser supports it, with WebP as a fallback and JPEG as a final fallback. This progressive approach ensures every visitor gets the smallest file their browser can handle.

For most site owners, starting with WebP is the practical move. It is fast to encode, universally supported, and delivers meaningful savings over JPEG. AVIF is worth adopting when your build pipeline and CDN support it.

Frequently Asked Questions