B8 · Performance & Mobile UX

    CDN Checker — are you serving content from the edge?

    A CDN serves your content from a server close to each visitor instead of one distant origin — cutting the latency that slows everyone far from your server. This check looks for signs your site is delivered through a content delivery network. Without one, a visitor on the other side of the world waits for every request to cross the planet and back; with one, they're served from a nearby edge.
    Updated June 2026 · Technical SEO & GEO · Part of Performance & Mobile UX

    Check your CDN usage

    Paste a URL — GEObubbly looks for signs your content is delivered through a CDN edge rather than a single origin.

    ✓ Free check1 signal✓ No signup required
    In short: A content delivery network serves your assets from a location near each visitor, cutting latency globally and absorbing traffic spikes.

    What does the CDN check look for?

    It looks for indicators that your content is delivered through a content delivery network rather than served directly from a single origin. Specifically:

    • CDN delivery — response headers and behaviour suggesting a CDN is sitting in front of your origin.
    • Edge caching — whether static assets appear to be cached and served from edge locations.
    • Distribution — whether content is positioned to be served close to users rather than from one distant server.

    Content delivered via a CDN passes; partial CDN use (some assets but not the main delivery) is a warning; no CDN, with everything served from a single origin, is a fail.

    How is it evaluated, and how is it scored?

    GEObubbly inspects response headers and delivery characteristics for signs of CDN use. It's an extended Performance check that runs partially, since detecting a CDN depends on how the live site responds.

    Why CDN usage matters for SEO and GEO

    A content delivery network is a global network of edge servers that cache and serve your content from a location physically close to each visitor. The benefit is latency: a request that would otherwise travel thousands of miles to a single origin and back is instead answered nearby, which lowers server response time and speeds up loading for users far from where your site is hosted. A CDN also offloads work from your origin (it serves cached assets so your server handles fewer requests), absorbs traffic spikes, and typically adds compression and modern protocols. For a site with a geographically spread audience, a CDN is one of the most effective performance upgrades available, improving Core Web Vitals for distant users in particular. It's not strictly required — a fast origin serving a local audience may not need one — which is why this is an extended rather than core check. For crawling, faster global delivery helps engines, including AI crawlers, fetch your pages efficiently wherever they request from.

    How this check scores
    Pass: Assets are served via a CDN.
    Warning: Mixed — some assets via CDN, some from the origin.
    Fail: No CDN; slow delivery for distant visitors.

    FAQ

    A CDN, or content delivery network, is a globally distributed network of edge servers that cache copies of your content close to where your users are. When someone requests a page or asset, the CDN serves it from the nearest edge location rather than from your single origin server, so the data travels a much shorter distance. This cuts latency and speeds up loading, especially for visitors far from your host. The CDN also offloads traffic from your origin and can absorb sudden spikes, making your site both faster and more resilient.

    Related checks in Performance & Mobile UX

    B2
    TTFB / server response speed
    B1
    Core Web Vitals (LCP, INP, CLS)
    B5
    Render-blocking resources & page weight

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