CDN – Content Delivery Network
A global network of servers that distributes content (images, video, JS) from the server closest to the visitor. Cuts load time by 40-70%, improves Core Web Vitals, and boosts SEO.
In practice
A CDN is the difference between a site that loads in 1.2 seconds and one that loads in 3.8. For a visitor in a city far from a US server, every image arrives from far away. With a CDN (Cloudflare, Fastly), images arrive from a local or regional server — a 60-70% improvement.
Common misconception
'CDNs are only for big sites.' Cloudflare's free plan is enough for most stores — $0/month. Shopify includes a built-in CDN. WooCommerce + Cloudflare drives a meaningful improvement. A CDN is one of the best-ROI optimizations available.
How to fix it
Site slow despite a CDN? (1) Check that the CDN is actually active (Cloudflare Dashboard → Cache Analytics), (2) Check cache-control headers — are images being cached? (3) Check image optimization — a CDN doesn't compress images automatically; it requires configuration.
Example
Computer-accessories store: page load time 4.1 seconds (US server, US customers). Added Cloudflare Pro ($20/month): load time 1.7 seconds. LCP went from 4.8s to 2.1s. Mobile organic traffic +31% within 60 days.
Priority
A CDN is priority 1 for technical optimization. Shopify: built in. WooCommerce: Cloudflare free plan + W3 Total Cache. 1 hour of setup = measurable improvement in Core Web Vitals, SEO, and CR.
Related terms
Keep learning. Metrics that touch the same area:
- Core Web VitalsSEOThree site performance metrics: LCP (main content load < 2.5s), INP (interaction responsiveness < 200ms), CLS (visual stability < 0.1). Google factors these into rankings.
- API – Application Programming InterfaceTechA 'language' for communication between systems. A store connects via API to shipping providers, Klaviyo, and payment platforms. The API is the 'pipe' through which data flows.
- Headless CommerceTechAn architecture that separates the front end (what the customer sees) from the back end (catalog, payments, inventory). Gives full freedom in design and channel integration.
- CRM – Customer Relationship ManagementTechA system for storing customer data, communication history, and purchase history. Enables segmentation, personalization, service tracking, and lifecycle management. HubSpot, Salesforce, Klaviyo.
- CDP – Customer Data PlatformTechConsolidates customer data from multiple sources into a unified real-time profile. More advanced than a CRM — pulls behavioral events and enables instant segmentation.
- Marketing AutomationTechSystems that trigger automatic marketing actions: cart abandonment → email, purchase → thank-you SMS, 90 days without a purchase → win-back campaign.
Jimmy tracks your CDN – Content Delivery Network, automatically
WhatsApp alerts when something important changes. No dashboards, no hassle.