WebP Image Format
WebP is a modern image format developed by Google that provides superior compression compared to JPEG and PNG — typically 25–35% smaller at equivalent visual quality. All modern browsers support WebP. Shopify automatically converts uploaded images to WebP when delivered through its CDN.
Why It Matters for Shopify Stores
Image size is the single largest contributor to page weight on most Shopify stores. A product page with 8 unoptimized product photos can easily weigh 3–5MB, resulting in 4–8 second load times on mobile. Shopify's CDN automatically serves WebP to browsers that support it (when you use the correct image_url filter in your Liquid templates). If your theme uses direct image URLs instead of Shopify's responsive image functions, you may be missing automatic WebP conversion.
How to Check Your Store
In Chrome DevTools Network tab, filter by 'Img'. Check the Type column — it should show 'webp' for most images. If you see 'jpeg' or 'png' primarily, your theme isn't using Shopify's responsive image functions correctly.
Use the free shopify speed test toolHow to Fix It
Ensure your theme uses the | image_url Liquid filter with width parameters rather than direct .jpg URLs. Most OS2.0 themes do this correctly. If on a legacy theme, update image tags to use Shopify's responsive image functions.
Related Terms
Image Optimization
PerformanceImage optimization is the process of reducing image file size without significantly reducing visual quality, while ensuring images are the correct format (WebP), dimensions, and compression for their use case.
Lazy Loading
PerformanceLazy loading is a technique where images and other resources are only loaded when they're about to enter the user's viewport — rather than all at once when the page first loads.
LCP (Largest Contentful Paint)
Core Web VitalsLargest Contentful Paint measures how long it takes for the largest visible content element on a page — usually a hero image or headline — to finish loading.
Shopify CDN
ShopifyShopify's CDN (Content Delivery Network) automatically serves your store's images, JavaScript, and CSS from servers geographically close to your visitors.
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