Performance

Content Delivery Network (CDN)

A CDN is a geographically distributed network of servers that caches and serves web content from the server closest to each visitor. CDNs dramatically reduce latency for static assets (images, CSS, JavaScript) by eliminating long-distance network travel.

Why It Matters for Shopify Stores

Shopify includes a global CDN (powered by Fastly) that automatically serves your store's assets from edge locations worldwide. This is one of Shopify's most significant infrastructure advantages — your product images load fast for visitors in Tokyo, Toronto, and London alike. Understanding the CDN helps merchants recognize why using Shopify's native image functions (which route through the CDN) is always better than hotlinking external images.

How to Check Your Store

In Chrome DevTools Network tab, check if image and asset URLs point to cdn.shopify.com. These are CDN-served. External images from other domains aren't served through Shopify's CDN.

Use the free shopify speed test tool

How to Fix It

Upload all images directly to Shopify rather than hotlinking external images. Use Shopify's Liquid image filters to ensure all images are served through the CDN with proper dimensions and WebP conversion.

Related Terms

Shopify CDN

Shopify

Shopify's CDN (Content Delivery Network) automatically serves your store's images, JavaScript, and CSS from servers geographically close to your visitors.

TTFB (Time to First Byte)

Core Web Vitals

Time to First Byte is the time between a user's browser making an HTTP request and receiving the first byte of data from the server.

Edge Caching

Performance

Edge caching stores copies of your store's pages, images, and assets at CDN edge servers around the world — so future requests are served from the closest edge location rather than your origin server.

WebP Image Format

Performance

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.

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