methodology / Performance / #32

Image optimization (WebP/AVIF)

live factor #32 · Performance · scoring impl: implemented · weight 1.3%

What we measure

Modern image formats (WebP, AVIF) are 30-70% smaller than JPEG/PNG with no visible quality loss. Most browsers support them; serving JPEG to everyone wastes mobile bandwidth.

How to improve your score

Use a `<picture>` element with WebP/AVIF sources, or switch to a host/CDN that auto-converts (Cloudflare Polish, image CDN like Cloudinary).

Data source

Data source for this factor is not yet documented.

Scoring

Scoring formulas are versioned with the methodology. The current method (v1.1.0) maps raw measurements to pass, warn, fail. Factor weights determine how much each contributes to the composite — see the methodology index for the full table.

Version history

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