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Speed

Images use an older, heavier format

What this means for your business

Your images use older formats (JPG or PNG) instead of the modern WebP format, which can be 25–35% smaller at the same visual quality. Switching format is one of the quickest ways to speed up page load without any visible change in how your site looks.

How to fix it
Easy
30–60 minutes

  1. 1WebP is a modern image format that produces files 25–35% smaller than JPG or PNG at the same visual quality. Converting your images is one of the quickest speed wins available.
  2. 2Upload your images to Squoosh (squoosh.app) — it's free. Select "WebP" as the output format, set quality to around 80, and download. Compare the before-and-after file sizes.
  3. 3Replace the original images on your site with the WebP versions. Update any hardcoded file references in your HTML or CMS if the extension changes.
  4. 4All modern browsers (Chrome, Firefox, Edge, Safari) support WebP — you don't need a fallback for most sites today.
  5. 5For bulk conversion, use a free desktop tool like XnConvert or the Squoosh CLI to convert many images at once.

On WordPress

Install Imagify, ShortPixel, or Smush — all have free tiers. They automatically convert images to WebP when you upload them and serve the WebP version to supporting browsers. No manual conversion needed.

On Shopify

Shopify automatically converts and serves images in WebP format when you upload them. If this issue still appears, look for images embedded directly in your theme code or blog content as hardcoded file paths — those bypass automatic conversion.

Pro tip: Start with your largest images first — hero images, product photos, and blog post thumbnails. These give the most size reduction per image converted.

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