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How to serve images in next-gen formats (WebP, AVIF)

Speed1 min readFixes check image-formats

WebP and AVIF are 25–50 % smaller than JPEG and PNG at the same quality. Converting the hero image alone often fixes LCP.

Step by step, with screenshots: How to fix Largest Contentful Paint (LCP), step by step →

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What a passing site looks like

  • Images are served in modern formats (WebP or AVIF)warning · −4 ptseffort S

Modern image formats

Why it matters. WebP and AVIF are 25–50 % smaller than JPEG and PNG at the same quality. Smaller images load faster and cost visitors less data.

How to fix it.
  1. Convert images to WebP or AVIF and serve them with <picture> or content negotiation.
  2. WordPress: enable WebP/AVIF in your image plugin or CDN (Imagify, ShortPixel, Cloudflare Polish); Shopify does this automatically for its CDN.

Filed under Speed & Core Web Vitals. Copy is generated from the same catalogue that scores every report, so what you read here is what the report says.