What are the best web performance monitoring tools for developers?

1 What is web performance monitoring?

Web performance monitoring is the process of collecting and evaluating data related to how your website or application performs on different devices, browsers, networks, and locations. Web performance monitoring can help you identify and resolve issues that affect your web performance, such as slow loading times, broken links, layout shifts, or security breaches. Web performance monitoring can also help you optimize your web performance by providing insights into how your users interact with your website or application, what features they use or ignore, and what expectations they have for your web performance.

3 What are the key web performance metrics for developers?

Web performance metrics are the indicators that measure how well your website or application performs on various aspects. Developers can use many web performance metrics, but some of the most common and important ones are load time, First Contentful Paint (FCP), Largest Contentful Paint (LCP), Time to Interactive (TTI), Cumulative Layout Shift (CLS), Speed Index, First Input Delay (FID), and Total Blocking Time (TBT). Load time is the amount of time it takes for your website or application to load fully on a user's device, while FCP is the time it takes for the first piece of content to appear on the screen. LCP measures the time it takes for the largest piece of content to appear on the screen, and TTI is the amount of time it takes for your website or application to become fully interactive and responsive. Additionally, CLS indicates the unexpected movement of elements on a page during loading or interaction, Speed Index is the average time it takes for visible parts of a page to be displayed, FID measures the time it takes for the browser to respond to a user interaction, and TBT is the total time that the main thread is blocked by long-running tasks that prevent user interaction.

4 How to measure web performance metrics?

To measure web performance metrics, you need to use web performance monitoring tools that collect and analyze data from various sources. Real User Monitoring (RUM) tools measure web performance metrics from actual users and can help you understand the effects of web performance on user behavior, satisfaction, and loyalty. Synthetic Monitoring (SM) tools measure web performance metrics from simulated users and can help you identify and fix any issues before they affect your real users. Web Performance Audits (WPA) tools measure web performance metrics from a single page or set of pages and can help you evaluate your web performance against best practices and recommendations.

5 What are the best web performance monitoring tools for developers?

There are several web performance monitoring tools available for developers, but some of the best ones are Google PageSpeed Insights, Lighthouse, WebPageTest, Pingdom, and New Relic. Google PageSpeed Insights provides a score for your web performance on mobile and desktop devices based on Core Web Vitals metrics. Lighthouse audits your web pages and provides reports on your web performance, accessibility, best practices, SEO, and progressive web app (PWA) quality. WebPageTest tests your web pages from multiple locations, browsers, devices, and connection speeds. Pingdom is a paid SM and RUM tool that monitors website or application uptime, speed, and user experience. New Relic is a paid RUM and SM tool that monitors website or application performance, availability, and reliability. All these tools also provide detailed information on your web performance metrics such as load time, FCP, LCP, TTI, CLS, FID and TBT. Additionally, they allow you to compare your web performance with other websites or competitors as well as track and optimize it over time and across different regions and devices.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?