WebP is Google's web image format from 2010 and is supported by effectively every current browser; AVIF is the newer AV1-based format that produces smaller files at the same visual quality. AVIF wins on compression, but it encodes slowly and has narrower support, so the practical default today is WebP, with AVIF layered on selectively by high-traffic sites.
Reducing image file size is key to speed up website loading. The long-standing JPG and PNG formats are paving the way for next-generation formats: WebP and AVIF. These formats offer superior compression ratios and play a crucial role in modern web optimization.
WebP: The Modern Web Standard
Developed by Google in 2010, WebP is about 25-34% smaller than JPG and 26% smaller than PNG at equivalent visual quality. It supports both lossy and lossless compression, transparency (alpha channel), and animations, making it an excellent all-rounder supported by almost all modern web browsers.
AVIF: The Ultimate Compression
AVIF is based on the AV1 video codec developed by the Alliance for Open Media. It compresses files 20-30% more than WebP does. It also handles fine details much better, supports HDR (High Dynamic Range) color, and features 10-bit/12-bit depth, which makes it ideal for top-quality photography and graphics.
WebP vs AVIF: Decision Guide
Here is how to make the right choice between the two next-gen formats:
- General Web Use: WebP is recommended as a safe default because of its universal browser compatibility and highly efficient size.
- Maximum Savings: If your audience uses modern platforms and every kilobyte counts, choose AVIF.
- Hybrid Strategy: Use the HTML <picture> tag to deliver AVIF to modern browsers, fallback to WebP for older ones, and JPG as a last resort.
Frequently asked questions
- If AVIF is better, why does everyone use WebP?
- Browser coverage and encoding speed. AVIF takes several times longer than WebP to compress the same image, which becomes a real server cost for image-heavy sites. Processing time, not storage, is often the actual bottleneck.
- Which is better for lossless storage?
- WebP is the dependable choice there. For text-heavy images such as screenshots, our measurements put lossless WebP at 17KB against PNG's 94KB, less than a fifth. AVIF supports lossless too, but its advantage in this territory is not clear-cut.
- How do I handle older browsers?
- Put several source elements inside an HTML picture element and the browser picks the first format it supports. List AVIF, then WebP, then JPG: modern browsers take the lightest file and older ones fall back to JPG.
- Should I use WebP for social posts and documents too?
- Better not. Outside the web, plenty of places still reject it: government submission forms, older document editors, and print shop intake rules among them. Keep files destined for submission as JPG or PNG.
