Marketing Monday: How To Run & Read A Google Lighthouse Audit

Originally Published November 2019

What we’re going to do today is explain what a Google Lighthouse audit is, why it’s important to your website and marketing initiatives, and how to decipher all of the data. Let’s run an audit, and learn how to read a Google Lighthouse audit together in this blog. Also, be sure to check out our YouTube video on the subject if you prefer to watch rather than read.

Title card reading: How to run and read a Google Lighthouse audit. With lighthouse graphic on grey background.

1. What Is Google Lighthouse?

It’s an open-source tool. It analyzes a single page of a website’s performance, like the Cohlab.com homepage or this blog page. It looks at that, but it’ll give you advice that can apply to an entire website.

When you go through, you’re gonna see that you can choose to simulate a weak 4G data connection from a mobile device when you’re analyzing the page. That’s what we do. It gives you the worst-case scenario for how your page is going to look. It gives you performance tips on a scale of 100. A score above 90 gets you in the top 5% of all websites.

2. Why Is Google Lighthouse Important?

Google Lighthouse is really approachable. It can be run and read straight from the Chrome browser.

It’s actionable: it gives you very specific advice.

And it’s authoritative: It’s built by Google devs who have deep insight into Google Chrome.

3. How Do You Read A Google Lighthouse Audit?

Freeze frame from video showing the run of a google lighthouse audit with Presenter's face in the corner, YouTube logo and Cohlab logo.

Let’s run an audit on Cohlab.com right now. 

  • Open a Chrome browser
    • On the right-hand side in the menu click “New Incognito Window”
    • Browse to your website
    • In the top-right go to the menu
      • Hover over “More Tools”, click ‘Developer Tools”.
        • Choose “Audits” in the top right
        • Choose mobile
        • Select all the audits
        • Simulated slow 4G
        • Clear storage
        • Run audits

It will take a minute or two to run through your whole page and reload it multiple times. What you’re going to see is a row of results across the top. And each one is clickable. They’ll bring you down to a section explaining those results in further detail.

Performance

The first thing we’re going to see come up here is “Performance”. We can click it, it just jumps down. 

“First contentful paint”, “first meaningful paint”, mean how long did it take til enough of the page is loaded that someone can recognize what is going on.

“Time to interactive” is how long did it take so that someone can click buttons, click in a menu, fill out a form, when was the site interactive. 

Accessibility

Further down is “Accessibility”. This is all about making sure everybody can use your website. Are the colors contrasted enough for people who maybe are color blind or have a hard time seeing. Do your images have alt-text so that a screen-reader can read that to a person who cannot see or has a hard time seeing that image. Do your links have names so people know where they’re going rather than it just saying “click here”.

Best Practices

“Best Practices” is below that. Do we have things set up properly in iFrames, do we have JavaScript libraries updated, do we have HTTPS set up.

Search Engine Optimization or SEO

“Search Engine Optimization” or “SEO” do we have buttons properly sized, do we have headers in place, are things described properly, is it mobile-friendly.

Progressive Web App or PWA

“Progressive Web App” or “PWA” is similarly overlapped with HTTPS, mobile-friendly tests, things like that.

That’s all for today, thanks for watching. Next week we’re going to cover what actions you can take based on this data. Please like and share our video with your friends if you learned something.

If you didn’t learn anything, ask us a follow-up question below, and we’ll answer as soon as we can. Also, be sure to like and subscribe to get the latest Marketing Monday every week.