Field Testing

Measure your site's performance as it works in the wild

What is Field Testing?

Field Testing quietly and non-obtrusively observes and sends anonymous performance data from the browser when your website or web application is used. Instead of only relying on synthetic data, this feature lets you know how fast your website loads in the wild.

It gives you valuable information about how fast our website really is, if there are any performance issues, and how you can make it even better. Importantly, Field Testing does not monitor or track your visitors or their behavior, maintaining their anonymity and privacy.

Set up Field Testing
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Field Testing with PageVitals

Analyzing your website in the wild is easy, fast and safe with PageVitals. Inject a small code into your website and:

  • Monitor you actual Web Core Vitals
  • Get page-by-page reports
  • Monitor resources and third-party scripts efficiently and effectively
  • Filter our your data to uncover insights based on region, device type, page and browser cache status
  • Add custom tags and variables
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How does Field Testing work?

Field Testing requires that you install a JavaScript code on your website. Once configured, you will start collecting anonymous performance data from real traffic. PageVitals' script is lightweight, privacy-fanatic and won't affect your site's loading speed in any noticeable way.

Here's how Field Testing works step by step:

  • Data Collection: When your website is used, the web browser automatically sends back information about how the website loaded and performed. This data includes details about page load times, server response times, network latency, and other performance-related metrics.
  • Privacy-fanatic: The Field Testing script does not collect any information about the user or the browsing behavior. No mouse or key events are tracked. No cookies are set so the script has no concept of a visitor or a session. Even the IP address of the browser is discarded on the edge. This is what we call privacy-fanatic and makes the feature compliant with most privacy frameworks around the world. In other words, we let you monitor your website's performance without monitoring visitors.
  • Data Aggregation: Real-world traffic data is aggregated and presented in charts. This provides a comprehensive view of how the website performs in the wild for different device types, regions, and network conditions.
  • Performance Analysis: The aggregated data is then analyzed to extract valuable insights into how the website is performing in the real world. Website owners and developers can see average load times and trends.
  • Geographical Insights: Field data can be broken down by geographic location, allowing businesses to understand how the website performs in different regions. This helps identify regional disparities in performance and optimize content delivery.
  • Device-specific Analysis: Field data also enables analysis based on different devices, such as desktops, smartphones, and tablets. This information helps optimize the website for each device type, considering factors like screen size and network capabilities.
  • Real-time Monitoring: Field data operates in real-time, which means website owners can receive immediate feedback on performance issues or outages. Real-time monitoring allows for quick responses to any emerging problems.
  • Long-term Trends: Field data can be analyzed over longer periods, allowing businesses to track performance trends and make informed decisions about optimization efforts over time.

Difference between synthetic and field testing

One of the main differences between synthetic testing and field testing, is that one is based on simulated, controlled tests, whereas the other is based on performance data of real traffic.

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Challenges and benefits of Field Testing

Challenges of Field TestingBenefits of Field Testing
1. Privacy and Data Protection: Field Testing involves collecting performance data from real browsers, which may raise privacy concerns (although PageVitals doesn't monitor or track users or user behavior).1. Accurate Insights: Field Testing provides real-world performance data on how your website actually loads, leading to accurate insights.
2. Technical Implementation Complexity: Setting up Field Testing requires proper integration and configuration.2. Comprehensive Performance Metrics: Field Testing provides a wide range of performance metrics, enabling a holistic view of website performance.
3. Impact on Website Performance: The Field Testing script may add a tiny overhead to the website.3. Real-world Geographical Insights: Field Testing data can be broken down by location, helping businesses understand performance from different regions.
4. Data Analysis Complexity: Interpreting Field Testing data may require data analysis skills and context understanding.4. Real Browsers Understanding: Field Testing data reveals how your website loads in the wild, helping businesses make informed decisions.
5. Difficulty in Isolating External Factors: External factors (e.g., slow internet connections) can affect Field Testing results.5. Objective Data for Decision Making: Field Testing provides objective data to guide website optimization and decision-making processes.
6. Limited Insight into Uncommon Devices: Field Testing may not capture performance data from all types of devices or browser combinations.6. Identifying Performance Bottlenecks: Field Testing helps pinpoint specific performance issues, enabling focused optimization efforts.
7. Need for Continuous Monitoring: Field Testing requires ongoing monitoring for long-term performance insights.7. Real-time Issue Detection: Field Testing operates in real-time, allowing businesses to quickly respond to performance problems or outages.
8. Cost and Resource Allocation: Implementing and maintaining Field Testing may involve costs and resource commitments.8. Continuous Improvement: Field Testing facilitates continuous optimization efforts, ensuring the website delivers a consistently excellent browsing experience over time.
9. Reliability and Data Accuracy: Field Testing data may vary based on geographical location and network conditions.9. Enhanced Browsing Experience: Field Testing enables businesses to enhance the overall browsing experience by addressing issues and optimizing performance.