> ## Documentation Index
> Fetch the complete documentation index at: https://docs.loadforge.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Core Web Vitals (CrUX)

> Monitor real user experience with Chrome User Experience Report data

Core Web Vitals are a set of specific factors that Google considers important for a webpage's overall user experience. LoadForge automatically collects and analyzes Chrome User Experience Report (CrUX) data to provide insights into how real users are experiencing your site.

## About CrUX Data

The **Chrome User Experience Report (CrUX)** collects anonymized, real-world performance data from Chrome users visiting your website. This provides valuable insights into actual user experiences rather than simulated tests.

<Note>
  CrUX data is updated monthly and requires sufficient traffic to your site to generate meaningful metrics. New or low-traffic sites may initially show "Insufficient data" for some metrics.
</Note>

## Key Metrics

<Frame caption="CrUX Metrics Dashboard">
  <img src="https://mintcdn.com/loadforge/-JPjrj7GdlQs4xIV/images/crux-metrics.png?fit=max&auto=format&n=-JPjrj7GdlQs4xIV&q=85&s=5adf47baa96222d9cce7a0d028dbb99a" alt="CrUX Metrics Dashboard" width="2854" height="1842" data-path="images/crux-metrics.png" />
</Frame>

### HTTP/S Performance

<Frame caption="HTTP/S Performance Metrics">
  <img src="https://mintcdn.com/loadforge/-JPjrj7GdlQs4xIV/images/crux-https.png?fit=max&auto=format&n=-JPjrj7GdlQs4xIV&q=85&s=ea49d67f91db176b2625680f5f7bbd3f" alt="HTTPS stats" width="2304" height="1038" data-path="images/crux-https.png" />
</Frame>

#### TTFB (Time to First Byte)

TTFB measures how long it takes for a user's browser to receive the first byte of response from your server after making a request.

* **Excellent**: Under 200ms
* **Good**: 200-500ms
* **Fair**: 500-1000ms
* **Poor**: Over 1000ms

<Tip>
  To improve TTFB, focus on server optimization, implement caching strategies, optimize database queries, or consider upgrading your hosting resources.
</Tip>

#### FCP (First Contentful Paint)

FCP measures the time from when the page starts loading to when any part of the page's content is rendered on the screen.

* **Good**: Under 1.8 seconds
* **Needs Improvement**: 1.8-3.0 seconds
* **Poor**: Over 3.0 seconds

### Web Performance

<Frame caption="Web Performance Metrics">
  <img src="https://mintcdn.com/loadforge/-JPjrj7GdlQs4xIV/images/crux-website.png?fit=max&auto=format&n=-JPjrj7GdlQs4xIV&q=85&s=660880d317f74a54870e550b8edbfd1b" alt="Web performance metrics" width="2299" height="1452" data-path="images/crux-website.png" />
</Frame>

#### LCP (Largest Contentful Paint)

LCP measures the time it takes for the largest content element visible in the viewport to be rendered.

* **Good**: Under 2.5 seconds
* **Needs Improvement**: 2.5-4.0 seconds
* **Poor**: Over 4.0 seconds

#### CLS (Cumulative Layout Shift)

CLS measures the sum of all unexpected layout shifts that occur during the entire lifespan of the page.

* **Good**: Under 0.1
* **Needs Improvement**: 0.1-0.25
* **Poor**: Over 0.25

#### INP (Interaction to Next Paint)

INP measures the responsiveness of a page by observing the latency of all interactions a user makes with it.

* **Good**: Under 200ms
* **Needs Improvement**: 200-500ms
* **Poor**: Over 500ms

## Tracking Changes Over Time

LoadForge stores and tracks CrUX results monthly, allowing you to:

* Monitor performance trends over time
* Identify seasonal patterns that affect user experience
* Measure the impact of optimization efforts
* Detect regressions after site updates

<Frame caption="CrUX Metrics Trend Analysis">
  <img src="https://mintcdn.com/loadforge/-JPjrj7GdlQs4xIV/images/crux-trends.png?fit=max&auto=format&n=-JPjrj7GdlQs4xIV&q=85&s=f42db6729daa379f8954730f8ed3fe4f" alt="CrUX Metrics Trends" width="2313" height="1369" data-path="images/crux-trends.png" />
</Frame>

## Sub-Page Analysis

LoadForge not only tracks your main domain but also analyzes performance for key sub-pages, helping you:

* Identify specific pages with performance issues
* Prioritize optimization efforts based on page importance
* Compare performance across different sections of your site

## Why Core Web Vitals Matter

Core Web Vitals are critical for both user experience and SEO:

* **Google Search Ranking**: Core Web Vitals are direct ranking factors in Google's search algorithm
* **User Engagement**: Better metrics correlate with higher engagement and lower bounce rates
* **Conversion Rates**: Faster, smoother experiences lead to higher conversion rates
* **Mobile Experience**: Particularly important for mobile users, who often have less patience for slow sites

## Impact on LoadForge Score

Core Web Vitals account for **40%** of your overall [LoadForge Score](/performance/loadforge-score), making them the most heavily weighted component of your site's performance rating.

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    Discover technical performance insights
  </Card>
</CardGroup>