Objective
Improve the mobile Core Web Vitals performance of a website where a large number of URLs were classified as Poor.
Before
During Investicate
After
My Contribution
- Investigated the mobile Core Web Vitals report and identified LCP as a major performance issue.
- Analyzed the affected URLs and investigated the underlying LCP bottlenecks.
- Identified the LCP element and key performance issues affecting rendering.
- Documented the findings and provided the technical issues to the development team.
- Coordinated with the developers while the identified performance issues were addressed.
Key Issues Identified
- LCP: 7.1s — target ≤ 2.5s
- Total Blocking Time: 2,640ms
- Time to First Byte: 1,960ms
- Document Request Latency: 1,949ms
- Render Blocking Requests: 980ms
- Unused JavaScript: 1,595 KB
- Unused CSS: 86 KB
Result
The mobile Core Web Vitals status improved from:
269 Poor URLs → 0 Poor URLs
The affected URLs moved into the Needs Improvement category, with 212 URLs shown as Needs Improvement in the later report.
Key Takeaway
Developed practical experience in Core Web Vitals diagnosis, LCP analysis, technical SEO auditing, and cross-functional collaboration with developers to resolve performance issues.