The four ratings (scale 0–100)
The analysis combines several individual measurements into each of these scores. The colour follows the thresholds: 90–100 green (good), 50–89 orange (needs improvement), 0–49 red (poor).
- Performance – How fast the page loads and responds. The score most visitors and Google go by.
- Accessibility – How well people with disabilities can use the page, for example regarding colour contrast, alt texts and keyboard operation.
- Best Practices – Technical soundness and security of the page, for example HTTPS, an error-free console and correctly embedded images.
- SEO – Whether the technical basics for good discoverability in search engines are met, for example meta data and crawlable links.
Core Web Vitals
The three metrics used to assess the user experience. They feed into the ranking.
- LCP – Largest Contentful Paint: Time until the largest visible element has loaded. Guideline: under 2.5 s is good.
- CLS – Cumulative Layout Shift: Measure of unexpected layout shifts while loading. Guideline: under 0.1 is good.
- TBT – Total Blocking Time: Period during which the page does not respond to input. In the lab test this value stands for later responsiveness. Guideline: under 200 ms is good.
Further metrics
Detail values that feed into the performance score.
- First Contentful Paint: Time until the first content becomes visible. Guideline: under 1.8 s.
- Speed Index: How quickly the visible area fills with content. Guideline: under 3.4 s.
- Time to Interactive: Time until the page is fully usable. Guideline: under 3.8 s.
- Total Blocking Time: see Core Web Vitals above.
ℹ️ Info: The values come from a lab test under standardised conditions. They show a page's potential and may differ in everyday use depending on device and connection.