What is Real User Monitoring (RUM)?

Published 03 September 2020 11:27 (4 minute read)

Since the latest Google update about Web Vitals, search trends show an interest in the optimization of real user experience. In this post, I'll explain what Real User Monitoring is and how you can use it.

Real User Monitoring (of short RUM) is a method to collect user experience from real visitors from your website and store it in an application. This lets you collect information about how the users experience the loading of your website.

RUM is trending

First, I've embedded a snippet from Google Trends where the latest search trends are shown.

Google Trends for Real User Monitoring

Google Trends for Real User Monitoring


Ps, here is the link to view the real time Google Trends report for the above dataset about the Real User Monitoring keywords.

What is Web Vitals?

First, an introduction to Web Vitals. What is this and how can you use them to improve your user experience on a website.

Web Vitals is an initiative by Google to provide unified guidance for quality signals that are essential to delivering a great user experience on the web.

Core Web Vitals is a subset of Web Vitals items (LCP, FID & CLS) that are the subset to focus on for 2020, they may change over time.

  • LCP: Largest ContentFul Paint
  • FID: First Input Delay
  • CLS: Cumulative Layout Shift

More information can be found on web.dev/vitals.

Why should you monitor user experience?

The simple answer, you want to earn money from your visitors. So why don't you want to know how they are experiencing your website?

When your visitors don't have a good experience on one of your pages it's unlikely they are willing to try or buy your product. The first experience they have with your (online-)business can come via your website.

How to monitor user experience?

Most modern browsers support a method to collect information from your website visitors like Google Analytics collects information about the visitors (or use a privacy-focused solution like Fathom Analytics). These statistics can be collected and stored on a system that collects all the user experience data. Based on this data you can make changes and see if those are improving the user experience on your website.

If you don't want to store, aggregate, and monitor this yourself you can use a SaaS solution that is doing this for you. You only have to pay for the pageviews you use and they are storing, aggregating, and monitoring the user experiences. The main benefit is you don't have to worry about servers that collect all this user information, they handle will do this for you.

SaaS solutions

When you search for RUM, you likely get the drink that's called "rum". But that's not what we need. We want "Real User Monitoring" solutions, so what are the possible SaaS solutions you can use on your site to collect user experience information?

Real User Monitoring vs. Synthetic Monitoring

The big difference between Synthetic and RUM is the fact that you influence the environment of the synthetic tests, you exactly know what the specifications and conditions are of the server/client that is running the test. In the case of RUM tests, the user environment is unknown, they could have a bad internet connection or a really old device with low specifications.

Some users even load your website (in the example hosted in Amsterdam) from a location on the other side of the world, let's say Sydney in Australia. When you don't use a CDN the requests have to travel half of the world, this leads to (milli-)seconds of waiting time.

You can do multiple things to reduce the load time what will improve the user experience. I've divided the improvements into 2 groups.

  1. server-side, for example: use a CDN, load balancer, DNS based server usage.
  2. client-side, reduce the image size, minimize the usage of CSS/JavaScript

Do you want to learn more about website optimization? Take a look at this blogpost from Cloudflare or visit web.dev for more tips/tricks about website optimization.

Browser loading predictions

Also, Google announced back in 2019 that it's testing a feature in the mobile browser Chrome to indicate loading time for that website based on other users' experiences. Based on the blue of green loading bar users can see how fast the page normally loads.

Google Chrome on mobile shows loading time (from blog.chromium.org)

Google Chrome on mobile shows loading time (from blog.chromium.org)

Do you want to learn more about Real User Monitoring or Synthetic Monitoring? Take a look at Astronatic Insights.

Robin Dirksen

Robin Dirksen

On my blog, you can find articles that I've found useful or wanted to share with anyone else.

If you want to know more about this article or just want to talk to me, don't hesitate to reach out.