www.edx.org speed test — 20 Oct 2026

What these numbers mean

• The first byte arrived in 252 ms. That is workable, and the cheapest win left is caching or a warmer connection.
• The page transfers 758.2 KB over 26 request(s). Images files are 34% of it, so resize and recompress the largest images before anything else.
• The HTML itself arrives gzip-compressed.
• It runs over HTTP/3, so the assets share a connection instead of opening one each.
• The largest element took 3.78 s to paint, past the 2.5 s threshold: usually a hero image that is too big or a render-blocking script in front of it.
• Layout stayed still (CLS 0.024), so nothing jumps under the reader's cursor.
• The main thread was blocked for 1.18 s, so taps and scrolling wait while scripts run.

Fix first: Render-blocking resources - 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.

Read on one shared server, not a visitor's phone: use it to compare pages against each other, not as a promise about every connection. We fix what these tests find.