Use Lighthouse to reproduce a problem
Lighthouse is a lab measurement: it evaluates a page in a test environment and reports performance metrics and diagnostics. That makes it useful for trying a change before release and examining a particular loading sequence.
Record the URL, mobile or desktop mode, and test date. Repeat a suspected problem with comparable settings. If removing a large image consistently improves the same metric, that is stronger evidence than comparing two unrelated screenshots. A Lighthouse score is a weighted performance result, not a percentage of visitors satisfied with your site.
Use field data to understand eligible visitor experiences
Chrome UX Report data describes aggregated experiences from eligible Chrome users. It can capture a broader mix of devices, networks, and interactions than a single lab run. Check its reporting period and whether the source has enough data for your URL.
An origin-level result includes a broader set of pages. For example, your light homepage and a heavy photo gallery may contribute different experiences to the same origin. Do not label an origin observation as a measurement of one service page. A newly improved page may also need time before a rolling field dataset reflects the change.
Investigate disagreement with a short decision log
If lab results are poor but field data is good, investigate what the lab setup exposes and whether important visitors still face that condition. If field results are poor but lab results look good, try other page templates and interactions rather than dismissing the field evidence.
Keep a simple comparison record. The goal is an explanation tied to a page or behavior, not a blended number that hides the disagreement.
- Exact tested URL and data scope: URL or origin.
- Device mode, measurement date, and available field period.
- The metric that differs and the customer action affected.
- One proposed change and how it will be evaluated.
Keep technical health and speed separate
ColbySEO's Technical score summarizes conclusive public technical checks with assessed-check and crawl coverage. It does not average Lighthouse and field categories into an overall website grade. When configured and available, PageSpeed measurements appear as separate evidence.
Begin with a free report if you need a shared record of public findings and checked URLs. Then use detailed performance tools and an actual phone test for the particular problem. Absent field data is not a failure, a pass, or evidence that every visitor has a good experience; it is a limit on what the source can establish.
Common questions
Which result should I trust?
Trust each within its scope. Use lab tests for diagnosis and repeatable comparisons, and available field data for eligible real-user experience over the stated period.
Can I average the two scores?
That would combine different evidence and conceal the useful differences. Keep the lab measurements and field categories labeled separately.
Why is there no field data for my small business site?
The data source needs sufficient eligible observations. A small or new page may not qualify even when it is public and loads normally.