Website Performance Monitoring

A performance monitoring tool with free and premium plans

Online Website Performance Monitoring Tool
Run a Free Website Performance Test
  • US East (N. Virginia)
  • US West (Oregon)
  • EU (London)

Foo is an online website performance monitoring tool that automatically audits web pages with Google's Lighthouse. We capture a variety of performance metrics and show them to you in a timeline chart.

Real time notifications!



You can configure email notifications by page. Supports multiple emails!


Automatic PagerDuty incident creation and resolution. Simple configuration with a simple "integration key".


Receive Slack notifications with a couple clicks! Choose any Slack channel or direct message notifications by page.


Our public REST API is free and publicly accessible. Trigger performance audits directly in your workflow like Jenkins, CircleCi, etc. Read more in our API docs.


An online website performance monitoring tool with a variety of features. Web page performance testing as a service.

  • check_circle_outlineAutomatic performance audits every 2 hoursstar
  • check_circle_outlineAutomatic Uptime checks every hourstar
  • check_circle_outline20 manual performance runs per daystar
  • check_circle_outline100 page limit, 25 user limitstar
  • check_circle_outlineChoice of regions to monitor from
  • check_circle_outlineReal time notifications by email, Slack, or PagerDuty
  • check_circle_outlineOnline monitoring and visualizations
Numbers vary by planstar

Lighthouse Performance Checks

Lighthouse website performance testing has become an industry standard practice among software engineering teams. Foo runs Lighthouse in the background and captures results automatically.

A Demo of How to Create a Page to Performance Audit Automatically

An example of how to use Foo's website performance monitoring tool. Create a page to run audits against. Monitor performance changes over time.

For more demos and other videos - head on over to the video page.

The free account features standard website performance monitoring with no limit or catch!

What is Website Performance?

Typically when we think of web page performance, we think of the time it takes for a page to load. Traditionally, we used JavaScript events on the window object such as DOMContentLoaded and onload. Nowadays, life cycle of a web page load can be thought of more granularly.

So rather than measuring load with just one metric, we should be measuring the times of every moment throughout the experience that can have an affect on the user's load perception.
~ User-centric Performance Metrics | Google Developers

What do we look for in web page performance testing? What ways can we measure performance? We can answer these questions more specifically by answering the following questions.

  1. What metrics most accurately measure performance as perceived by a human?
  2. How do we measure these metrics on our actual users?
  3. How do we interpret our measurements to determine whether an app is "fast"?
  4. Once we understand our app's real-user performance, what do we do to prevent regressions and hopefully improve performance in the future?

What are Website Performance Metrics?

We can think of website performance metrics as being "user-centric". When a user goes to a web page, they're typically looking for visual feedback to reassure them everything is working as expected.

The metrics below represent important points of the page load life cycle. Each answers questions about the user experience.

  • First Contentful Paint: Is it happening? Did the navigation start successfully? Has the server responded?
  • First Meaningful Paint: Is it useful? Has enough content rendered that users can engage with it?
  • Time to Interactive: Is it usable? Can users interact with the page, or is it still busy loading?
  • Long Tasks (absence of): Is it delightful? Are the interactions smooth and natural, free of lag and jank?

About Foo

Website testing as a service is a focus of Foo. Performance and uptime monitoring, among other aspects of software engineering is at the core of this service. Foo was founded by Adam Henson, a software engineer based in New York City. Follow Adam on Medium at @adamhenson or read an introduction to Foo on freeCodeCamp, "How to analyze website performance with Lighthouse".