PageSpeed Quick Check

Name: PageSpeed Quick Check | Core Web Vitals Analysis | SERPInsight
Author: SERPInsight

Instantly analyze your Core Web Vitals and performance score using Google's Lighthouse API. Compare Mobile vs. Desktop results in real-time.

Enter Website URL

https://

Results for:

Performance

Accessibility

Best Practices

SEO

Performance Score

Weighted average of metric scores. Focus on improving the metrics below.

First Contentful Paint First image/text visible.

Largest Contentful Paint Main content load time.

Total Blocking Time Responsiveness delay.

Cumulative Layout Shift Visual stability.

Speed Index Visible population rate.

Rendered Screenshot

Captured at: User Agent: Lighthouse:

What does this tool do?

The SERPInsight PageSpeed Quick Check connects directly to Google's API to perform a comprehensive performance audit of any webpage. It simulates how your site loads on both mobile devices (via 4G throttling) and desktop computers.

Beyond a simple speed score, this tool breaks down the "User Experience" using Core Web Vitals: Largest Contentful Paint (LCP), Cumulative Layout Shift (CLS), and Total Blocking Time (TBT). These are the exact metrics Google uses for ranking signals.

How to use it

1

Enter URL

Paste the full webpage address (e.g., https://example.com) into the input field above.
2

Run Analysis

Click "Analyze". The tool will fetch both Mobile and Desktop data simultaneously in the background.
3

Review & Compare

Use the toggle to switch between Mobile and Desktop views. Check the colored metrics to find bottlenecks.

How to read the scores

90 - 100 (Good)

The page is performing optimally. This is the goal for a competitive user experience.

50 - 89 (Needs Work)

The page loads but has significant delays or shifts that may frustrate users.

0 - 49 (Poor)

Critical performance issues detected. These pages likely fail Core Web Vitals assessments.

Metrics (LCP/CLS)

LCP measures loading speed. CLS measures visual stability. TBT measures interactivity.

Frequently Asked Questions

Why is my mobile score lower than desktop?

Mobile devices usually have slower processors than desktops, and Google's test simulates a mid-range phone on a 4G connection. This environment is much stricter, meaning unoptimized code or large images hurt the score more on mobile.

Does PageSpeed affect my Google Ranking?

Yes. Since the "Page Experience Update," Google uses Core Web Vitals (LCP, CLS, and FID) as ranking signals. A better score improves your chances of ranking higher, especially in mobile search results.

What is Cumulative Layout Shift (CLS)?

CLS measures how much the page "jumps" while loading. If text moves when an image loads or a banner appears, that's a layout shift. A good CLS score is 0.1 or less.

How often can I run this test?

You can run it as often as you like! It's useful to run a test, make changes to your website (like compressing images), and then run the test again immediately to see the improvement.

Why use this tool?

Professional insights for better web performance.

Accurate Data

We pull data directly from Google's Lighthouse API v5, ensuring you see exactly what Google sees when crawling your site.

Mobile-First Focus

Since most traffic is mobile, we prioritize mobile testing to help you optimize for the most critical user segment.

Actionable Metrics

We don't just give a grade; we isolate LCP, TBT, and CLS so you know exactly which technical area to fix.

Bot Simulation

See your site through the eyes of a crawler. The "Rendered Screenshot" feature proves exactly how your page loads.

PageSpeed Quick Check

Performance Score

Rendered Screenshot

What does this tool do?

How to use it

Enter URL

Run Analysis

Review & Compare