Measured PageSpeed data, not estimated scores
SEO Mentor runs a PageSpeed measurement for the URL and reports the returned Lighthouse performance, accessibility, best-practices and SEO scores. Lab metrics and optimization opportunities come from the measured test rather than HTML-count estimates.
Lab data and real-user data are different
Lighthouse lab metrics are generated during the current test. Real-user Core Web Vitals, when available for the page or origin, represent aggregated user experience. Some URLs do not have enough eligible field data, so SEO Mentor clearly marks field data as unavailable instead of inventing values.
Use performance evidence with a wider SEO review
Page speed is one part of technical SEO. Review performance findings together with crawlability, indexability, content quality, search intent and internal structure before prioritising changes.
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Frequently asked questions
Can I test mobile and desktop?
Yes. Select Mobile or Desktop before running the test. Each device strategy is measured separately.
Why might Core Web Vitals field data be unavailable?
Not every page or origin has sufficient eligible real-user data. The tool still reports the measured Lighthouse lab results and clearly separates them from field data.
Can PageSpeed results change between tests?
Yes. Lab measurements can vary with test conditions, page behaviour and third-party resources. Use repeated measurements and real-user data, when available, to judge sustained performance.