Lighthouse LCP and FCP
When Lighthouse reports them as findings, LCP indicates when the largest visible content appears and FCP when the first content is displayed. Read the available numeric values and units alongside the measurement profile.
Automated checks on a public URL
Website page speed test
Measure how a URL loads and identify the resources to examine first.
A laboratory measurement of one public page. Browser conditions and available modules matter; this test does not measure your users’ actual visits.
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This form runs the existing Argos audit across its four domains. Results include the available checks, their evidence and their limits.
What you can read in the report
Browser loading
The runtime module records loading events, errors and failed requests, as well as estimated response sizes. It does not provide field INP data.
Scores and timings
The Lighthouse Performance score is a mark out of 100, not a duration. The Argos Performance score combines separate weighted checks; do not convert either score into seconds.
Example: main content appears late
Fictional data, with no customer measurements. Assume a Lighthouse laboratory run on atelier.example with a declared desktop profile; always compare the same profile and conditions.
Illustrative evidence
largest-contentful-paint numericValue: 2800 numericUnit: millisecond LCP: 2.8 s
How to read it: 2,800 milliseconds correspond to 2.8 seconds for this run. A single measurement does not describe the 75th percentile of visitors or every mobile condition.
Suggested correction: Identify the LCP element and its loading chain, then examine image size, server delays and blocking resources before choosing an optimization.
What to check next: Run the same URL with the same profile again, compare several measurements and examine field data if you have it.
Limits to keep in mind
A run can vary with the network, content, cache and available services. Argos does not provide CrUX data collection, visitor INP or a guarantee of mobile speed here. A missing check is not a favorable result.