Lab Data vs Real User Data
Understanding the difference between lab data and real user data is crucial for optimizing your website's performance and improving your Core Web Vitals (CWV) scores. PerfBee's Real User Monitoring (RUM) dashboard provides both, allowing you to gain a comprehensive view of your site's performance.
Lab Data
Lab data refers to the results from simulated performance tests, specifically the Lighthouse audits that PerfBee's Performance Boost product provides. These audits run under controlled conditions, using a simulated device and network. This ensures reproducible results, making it ideal for debugging performance issues. The lab environment uses a throttled Moto G4 simulation.
Real User Data (Field Data)
Real user data, also known as field data, is collected from your actual website visitors using the lightweight JavaScript snippet installed through the RUM product. This data reflects the actual experience of your users, including their device, connection speed, and browser. Google uses this real-world data to assess your Core Web Vitals for ranking.
Why Lab and Field Scores Differ
Lab and field data often differ because of the controlled environment of lab tests versus the variability of real-world conditions. Factors such as device type, network connection, and content delivery can significantly impact performance. The simulated Moto G4 device in the lab environment may not accurately reflect the experience of all your users.
PerfBee's Lab vs Real Comparison Widget
PerfBee's RUM dashboard includes a 'Lab vs Real' comparison widget. This widget displays your latest Lighthouse LCP (Largest Contentful Paint) and CLS (Cumulative Layout Shift) scores from your Performance Boost audits alongside the P75 percentile values from real users collected by the RUM script. This allows you to quickly identify discrepancies between simulated and real-world performance.
When to Use Lab Data vs RUM Data
Use lab data for:
- Debugging performance issues.
- Testing potential fixes.
- Reproducing and isolating problems.
Use RUM data for:
- Monitoring real user experience.
- Understanding how users are actually experiencing your site.
- Validating the impact of your optimizations.
P75: The Google Standard
Google uses the 75th percentile (P75) of your real user data for Core Web Vitals ranking assessment. This means that Google considers the performance experienced by the majority of your users. PerfBee's RUM dashboard displays the P75 values for LCP, CLS, and INP (Interaction to Next Paint), giving you a direct view of the metrics Google uses to evaluate your site.
Using Both Together
The most effective approach is to use both lab and RUM data in conjunction. Use lab data to identify and debug performance issues, and then use RUM data to validate that your fixes are improving the real-world experience for your users. This combined approach allows you to achieve the best possible performance and user experience.