Definition
Page Speed
How fast a webpage loads and becomes interactive. Every second of delay reduces conversions by approximately 7%. Critical for mobile CRO.
What does Page Speed mean?
Page speed measures how quickly a webpage loads and becomes usable, typically assessed through metrics like Largest Contentful Paint and Time to Interactive rather than a single overall number. It reflects both server response time and how efficiently a page's assets are delivered and rendered.
Why does Page Speed matter?
It matters because slow-loading pages lose visitors before they ever see a headline, offer, or trust signal, and because search engines factor page speed into ranking, meaning slow pages also get less organic visibility to begin with. Mobile connections make this effect more pronounced than on desktop.
How is Page Speed applied in practice?
Page speed is measured using tools such as Lighthouse or Core Web Vitals reports, and improvement efforts, like image compression or reducing third-party scripts, are validated by remeasuring load times and checking whether bounce rate or conversion rate improves afterward.
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Where this fits
Page Speed sits in the conversion rate optimization part of the NotiProof resource network.
Read the Conversion Rate Optimization guide