Page Speed Checklist & Web Vitals Review
Build a page-specific performance plan from the page type, rendering model, assets, and optional measured Web Vitals, then track and copy the exact prioritized checklist.
- Context-Aware Priorities
- Web Vitals Review
- Interactive Progress
- Exact Action Report
- Rating-Gated Copy
Choose an action to generate output.
What is the Page Speed Checklist?
The Page Speed Checklist turns page context into a prioritized manual performance plan. It combines always-relevant measurement, loading, JavaScript, CSS, layout, network, regression, and quality checks with extra actions for the selected page type, rendering model, device target, images, video, fonts, third-party scripts, ads, and animations.
This browser-side tool does not request the URL, run Lighthouse, access Chrome User Experience Report data, or calculate a synthetic performance score. Optional LCP, INP, and CLS values are interpreted exactly as entered. Use real-user field data to understand production experience and controlled lab tests to diagnose issues and prevent regressions.
How to build a page speed action plan
- Name the page or user flow, optionally add its absolute URL, and select the page type, target devices, rendering model, and current workflow stage.
- Select only the characteristics that apply: images, video or embeds, web fonts, third-party scripts, ads or dynamic slots, and animations. Add known bottlenecks or delivery constraints.
- Optionally enter measured LCP in seconds, INP in milliseconds, and CLS as a unitless score. Identify whether the values are field data at the 75th percentile, a lab run, or an unknown or mixed source.
- Build the checklist, filter it by priority, category, status, or search text, and mark actions complete only after the listed verification step passes.
- Review the Web Vitals and exact Report tabs, then use Copy checklist. The first valid Copy uses the existing one-time rating flow and the clipboard text always matches the visible report.
Benefits of this performance planning workflow
- Generate page-specific tasks for landing pages, ecommerce, articles, interactive tools, dashboards, static output, server rendering, client rendering, and WordPress or CMS stacks.
- Prioritize measurement, LCP discovery, render-blocking CSS, long JavaScript tasks, layout stability, caching, compression, resource budgets, and regression monitoring.
- Add conditional actions for responsive images, LCP images, video, fonts, third-party tags, ad slots, animations, data-heavy dashboards, and expensive tool processing.
- Interpret user-supplied LCP, INP, and CLS values with good, needs-improvement, and poor states while keeping field and lab evidence clearly separated.
- Track completion, filter the working list, and keep each action paired with a reason and a concrete verification step.
- Copy one exact text action plan after the existing rating flow; no unreliable Download action or fabricated live measurement is shown.
Page Speed Checklist FAQ
Does this tool test my URL or run Lighthouse?
No. It does not request the page, run a browser trace, query PageSpeed Insights or CrUX, inspect network responses, or calculate a performance score. It creates a manual plan from the context and measurements you enter.
What are the current good Core Web Vitals thresholds?
A good LCP is 2.5 seconds or less, a good INP is 200 milliseconds or less, and a good CLS is 0.1 or less. Field assessment should use the 75th percentile of page loads and segment mobile and desktop.
Are lab and field results interchangeable?
No. Lab tests provide controlled diagnostics and regression signals. Field data captures real users, devices, networks, caches, and interactions. Lighthouse cannot directly measure real-user INP without user interaction and may use supporting lab diagnostics instead.
What does the readiness percentage mean?
It is only the percentage of generated checklist actions marked complete. It is not a page speed, Lighthouse, SEO, ranking, or Core Web Vitals score.
Why can the checklist change when I edit inputs?
The plan includes conditional tasks for the selected page type, rendering approach, device target, characteristics, and entered Web Vitals. Actions that no longer apply are removed along with their completion state.
Should I optimize only for Core Web Vitals?
No. Core Web Vitals cover loading, responsiveness, and visual stability, but a complete workflow should also consider reliability, accessibility, business journeys, server and network cost, regressions, and representative users.
Why is there no Download button?
The exact plan is available through one dependable Copy checklist action. The existing one-time rating gate runs before the first valid copy on that browser.
Help us improve this tool
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