To be effective in improving performance, we need metrics that accurately describe the user experience. If we can’t quantify the quality of customer experience, it won’t be easy to act on it.
The landscape of performance metrics changes rapidly. New metrics are introduced, and old, unreliable metrics are deprecated (for example, most recently, First Meaningful Paint). It’s critical to choose metrics that span over the entire spectrum of user experience:
Three of those metrics—LCP, TBT and CLS are defined as Core Web Vitals. Every team should track this set of measurements as they provide a birds-eye view of several facets of user experience.
Additionally, we recommend adding Lighthouse Scores and selected Paint and Request metrics to your arsenal. Learn more about the metrics Calibre can track.