--- title: GA4: Core Web Vitals Report – Speed ​​Monitoring url: https://blog.krasovskiy.team/en/ga4-core-web-vitals-report-speed-monitoring/ date: 2025-10-07 lang: en source: blog.krasovskiy.team --- # GA4: Core Web Vitals Report – Speed ​​Monitoring In the era of digital transformation, site speed has become a critical success factor for online business. GA4 (Google Analytics 4) in combination with [Core Web Vitals](https://blog.krasovskiy.team/en/core-web-vitals-what-it-is-and-how-it-works/) metrics provides a powerful toolkit for comprehensive monitoring of the speed of your web resource. Core Web Vitals is a set of key metrics from Google that measure the actual [user experience](https://blog.krasovskiy.team/en/digital-marketing-what-it-is-and-how-it-works/) of interacting with a site. These metrics directly affect search engine rankings and visitor conversion. GA4 allows you to track these metrics in real-time, providing detailed analytics on the performance of each page. ![](https://blog.krasovskiy.team/wp-content/uploads/2025/10/google-analytics-4.jpg) Speed monitoring through GA4 helps identify problem areas, analyze page load trends, and make informed decisions about optimization. The integration of Core Web Vitals into GA4 reports creates a single ecosystem for analyzing technical metrics and user behavior, enabling a comprehensive approach to improving site speed and increasing visitor satisfaction. ## What are Core Web Vitals in GA4 Core Web Vitals are a set of key website performance metrics that Google has determined are critical to providing a quality user experience. In the context of GA4 analytics, these indicators have become an integral part of site performance monitoring and affect ranking in search results. The main Web Vitals metrics include three main indicators. The first is Largest Contentful Paint (LCP), which measures the load time of the largest visible element on the page. The optimal LCP value should be less than 2.5 seconds from the start of page loading. This indicator directly affects the perception of site speed by users. The second important metric is First Input Delay (FID), which tracks the time from the user's first interaction with the page to the moment when the browser can actually react to that action. A good FID indicator should not exceed 100 milliseconds, which provides a sense of instant reaction of the site to the actions of the visitor. The third key indicator - Cumulative Layout Shift (CLS) measures the visual stability of the page. It captures unexpected displacements of elements when loading content. The optimal value of CLS should be less than 0.1, which guarantees a stable and predictable interface for users. With GA4, Core Web Vitals analytics are integrated directly into user engagement reports. This allows marketers and developers to get a comprehensive picture of how a site's technical performance affects visitor behavior, conversions, and the overall effectiveness of business goals. The role of these metrics in Google Analytics 4 goes far beyond simple monitoring. They help identify problematic pages, segment users based on the quality of their experience, and make informed optimization decisions. Integrating Core Web Vitals with other GA4 metrics creates a powerful tool for improving user experience and increasing your site's organic search rankings. ### Core Web Vitals Core Web Vitals consists of three key metrics that comprehensively evaluate the **speed** and quality of your site's user experience. Each metric is responsible for a separate aspect of the user's interaction with the page. **LCP (Largest Contentful Paint)** measures the loading time of the largest visible element on the page. It can be an image, a video, or a large text block. The optimal LCP indicator is less than 2.5 seconds. A slow LCP leads to a high bounce rate because users don't have to wait long for content to load. **FID (First Input Delay)** tracks the delay between the user's first interaction with the page (click, touch) and the browser's response. A good FID is less than 100 milliseconds. High FID values create a feeling of "freezing" of the site and negatively affect the user experience. **CLS (Cumulative Layout Shift)** measures the visual stability of a page during loading. The optimal CLS indicator is less than 0.1. A high CLS means that page elements shift during loading, which can lead to accidental clicks on the wrong buttons. These three metrics directly affect Google rankings and conversions. Sites with optimal Core Web Vitals scores get an advantage in search results and provide a better user experience. ### Why Core Web Vitals are important for SEO Core Web Vitals have become a critical factor for search engine optimization since Google officially included them in the ranking algorithm in 2021. These metrics directly affect your site's position in search results and shape the overall user experience. The impact of Core Web Vitals metrics on SEO is manifested through Google's Page Experience algorithm. Sites with better speed scores gain a ranking advantage over slower competitors. This is especially noticeable in competitive niches, where the speed of the site can be a decisive factor for getting into the top results. Site speed directly affects user behavior. Research shows that a 1 second load delay results in a 7% drop in conversions. Users expect instant site response, and if a page takes longer than 3 seconds to load, more than half of visitors leave it. Search engine optimization today is impossible without attention to technical aspects. Core Web Vitals help create a fast, stable, and user-friendly site that positively impacts bounce rate, time on site, and browsing depth. These behavioral factors, in turn, further improve positions in search engines, creating a positive cycle of organic traffic growth. ## How to set up a Core Web Vitals report in GA4 Configuring GA4 to monitor Core Web Vitals is an important step to effectively track your site speed. Google Analytics 4 provides powerful performance analysis tools to help you identify problematic pages and improve user experience. Before starting the setup, make sure you have access to a Google Analytics 4 account with administrator or editor rights. The Core Web Vitals report automatically collects data after proper configuration. 1. **Sign in to Google Analytics 4**. Open a GA4 account and select the desired resource for which you want to configure speed monitoring. 2. **Go to the "Reports" section**. In the left menu, click on Reports, then expand the Lifecycle section and find the Engagement subsection. 3. **Find the Pages and Screens report**. This report provides basic information about the performance of individual pages on your site. 4. **Enable Web Vitals data collection**. Go to Admin → Data Streams → choose your web stream → enable Advanced Measurement → make sure the Page Interactions option is active. 5. **Configure custom settings**. Under Configuration → Custom Definitions, create settings for LCP, FID, and CLS, if they haven't already appeared automatically. 6. **Create a custom Core Web Vitals report**. Use Research → Blank Research → add LCP, FID, CLS metrics and Page Title parameter. 7. **Configure filters and segments**. Add filters to display only those pages that have enough data to analyze. 8. **Save and share the report**. Once set up, save the report for regular use and share with team members. After completing these steps, Google Analytics 4 will begin collecting Core Web Vitals data. It usually takes 24-48 hours to see the first results. Check the Core Web Vitals report regularly to identify performance issues and track improvements after optimization. ### Connection of required events and parameters To effectively monitor Core Web Vitals through GA4, you need to properly configure events and data collection options. The process of setting up tracking begins with the activation of advanced measurements in the Google Analytics 4. property Go to Admin → Streams → select your web stream. In the flow settings, activate the Advanced Measurements option and make sure that the collection of user interaction events is enabled. This will automatically capture basic GA4 events needed for velocity analysis. For detailed tracking of Core Web Vitals, add custom parameters via Google Tag Manager or directly in your site code. Key parameters include: web_vitals_measurement for LCP, web_vitals_fid for FID and web_vitals_cls for CLS. Each parameter must pass numeric metric values. Setting up tracking also requires creating custom dimensions in GA4. Go to Settings → Custom Definitions → Create Custom Dimension. Add dimensions for each Core Web Vitals metric with appropriate parameter names. After completing the settings, check the correctness of data collection through DebugView in GA4. This will help ensure that all events and parameters are correctly transmitted and captured by the analytics system for further monitoring of your site's speed. ### Creating and customizing a report in GA4 To effectively monitor Core Web Vitals in GA4, you need to create a custom report that will allow you to visualize and analyze site speed data. Consider the step-by-step instructions for creating a report. Start by creating a report through the Research section of the GA4 interface. Choose the "Arbitrary shape" template for maximum flexibility of settings. In the left panel, add the required parameters: page/screen, traffic source and user device. To configure Core Web Vitals metrics in GA4, add LCP, FID, and CLS metrics by searching in the metrics section. It is important to include the 75th percentile segmentation to get a real picture of the user experience. Data visualization plays a key role in performance monitoring. Use combined graphs to display trends, tables for detailed page analysis and heat maps to identify problem areas. Configure filters to exclude internal traffic and focus on target audience segments. Save the created custom report as a template for regular use. Set up automatic data updates and report exports for the development team. ## Interpreting and analyzing Core Web Vitals data in GA4 Correct interpretation of Core Web Vitals data in Google Analytics 4 is key to effectively improving your website's performance. Understanding how to read and analyze these metrics will help you make informed optimization decisions. When analyzing Core Web Vitals data, pay attention to three main metrics: LCP (Largest Contentful Paint), FID (First Input Delay), and CLS (Cumulative Layout Shift). Each of them has its own threshold values: a good result for LCP is less than 2.5 seconds, for FID - less than 100 milliseconds, and for CLS - less than 0.1. Start the interpretation by identifying the problem pages. In the GA4 report, filter out pages with poor Core Web Vitals and analyze their common characteristics. These can be pages with a lot of images, video content or complex scripts. To improve LCP performance, optimize the loading of the largest content element. Use new generation image formats, configure lazy loading and minimize server response time. Browser caching and using a CDN will also improve this significantly. To improve FID, reduce JavaScript execution time. Break long tasks into smaller parts, defer non-critical JavaScript, and use web workers for heavy calculations. Remove unnecessary extraneous scripts that block the main thread. Always specify dimensions for image and video elements to optimize CLS. Avoid dynamically inserting content over existing content and use transform instead of properties that cause the layout to be rearranged. Regular analysis of Core Web Vitals data will help identify trends and seasonal fluctuations in performance. Create a dashboard to monitor key metrics and set up automatic alerts when performance deteriorates. Compare data with previous periods and monitor the impact of the changes made on the overall performance of the site. ### Identifying problem pages Effectively identifying **problem pages** with low **Core Web Vitals** is critical to improving **site speed**. The **GA4 report** provides powerful tools to quickly find such pages and prioritize them for optimization. To get started, go to Lifecycle → Interaction → Pages and Screens in your GA4. Next, click on the comparison icon in the upper right corner and select the Core Web Vitals metric. This will allow you to filter pages by their performance metrics. Pay attention to the pages with the worst LCP (more than 2.5 seconds), FID (more than 100 milliseconds) and CLS (more than 0.1). These are the pages that need immediate attention as they have the biggest impact on overall site speed and user experience. Use segmentation by device type to identify specific issues on mobile or desktop. Often problematic pages on mobile devices differ from desktop pages due to differences in processor power and Internet speed. Create custom alerts in GA4 to automatically monitor when Core Web Vitals drops below set thresholds. This will help to quickly respond to performance degradation and maintain high loading speed of all important pages. ### Recommendations for improving speed Improving site loading speed is a critical factor for successful SEO and a positive user experience. Optimizing a site to meet Core Web Vitals standards requires a comprehensive approach and the use of various techniques. To improve the Largest Contentful Paint metric, it is recommended to optimize images through compression services, use modern WebP or AVIF formats, and implement lazy loading. Setting up a CDN will significantly speed up the delivery of content to users in different regions. First Input Delay can be improved by minifying JavaScript code, removing unused scripts, and delaying the loading of non-critical resources. Splitting large JavaScript files into smaller modules also has a positive effect on response speed. To optimize Cumulative Layout Shift, it is important to always specify dimensions for images and videos, avoid dynamically inserting content over existing content, and use CSS transformations instead of changing layout properties. Useful tools for monitoring and improving Core Web Vitals include PageSpeed Insights, GTmetrix, and WebPageTest. Regular speed testing and implementation of the recommendations of these services will help maintain high performance of the site and improve its position in search engines.