home.cern speed test — 20 Oct 2026

The first byte arrived after 597 ms. Of that, 375 ms was the server thinking and 222 ms was connection setup. A first byte under 400 ms is what a visitor feels as instant.

Fix: Cut server think time: page cache, query indexes, fewer synchronous calls to third parties inside the request. Connection setup is distance, so a nearer region or a CDN edge helps instead.

7 image(s) over 200 KB and 10 large image(s) still served as JPEG or PNG.

Fix: Serve WebP or AVIF with a JPEG fallback, size images to the space they occupy, and lazy-load anything below the fold. Images are usually more than half of a slow page.

67 render-blocking resource(s) in the document head (52 script(s), 15 stylesheet(s)). The page cannot paint until each one arrives.

Fix: Add defer or async to scripts that do not change the first paint, inline the critical CSS, and load the rest with media="print" plus an onload swap.

The page transfers 7.99 MB across 26 request(s), with the document itself at 52.7 KB.

Fix: Work through the heaviest assets first: images, then fonts, then third-party scripts.

3 asset(s) answer without a Cache-Control max-age, so browsers revalidate them on every visit.

Fix: Version filenames on change and serve them with a long max-age plus immutable. That is what makes a returning visitor fast.