Lighthouse Analysis for SEO and Chrome | ®

light house and seo

We are going to delve a little into one of the tools that has accumulated the most weight in recent times: light house. Google’s beacon has crept into the day-to-day life of almost any digital marketing professional concerned with attending to and monitoring the health of their website in the eyes of the giant. Specifically, for SEOs it has become a practically essential indicator when it comes to optimizing what is known in the world as WPO (Web Performance Optimization).

“And what do you think of the lighthouse? Do you really think that there is a group of mad scientists,… «(Shutter Island2010. Martin Scorsese)

What is Lighthouse for Chrome?

Definition: It is a Google ecosystem tool integrated into the Chrome browser that audits any page of a site online, offering optimization metrics by area (Performance, Accessibility, SEO) and giving indications to follow the best web practices in order to increase satisfaction. of the user. All this shown in an online report that can be obtained in just a few seconds after activating the tool.

How to activate and install Lighthouse in Chrome?

Let’s say Lighthouse is already built into Chrome. You just need to know where to find it. To do this, we must locate ourselves on any web page that we want to audit and select the option to inspect element with our mouse or touch pad. The code and elements window will open. Several sections will appear in the horizontal menu (Elements, Console, Sources, etc.) and we will have to click on Audits. This is where Lighthouse is integrated and where we will be shown some configuration options for the tool to specify in the audit that we are about to carry out.

♦♦♦ Watch out! Like virtually all WPO auditing tools, the results are for a specific url and not for the entire web. It is a very typical mistake to run the tool through the Homepage and draw general conclusions for the entire site. From the point of view of an audit, our advice is to audit by type of page (Home, contact, category, product, post, etc.) or audit some specific pages that interest us by strategy. Of course there will be optimizations or improvement points that apply to the entire web, but we must bear in mind that the results will vary significantly depending on the page we audit. ♦♦♦

Going back to the tool settings. We will be able to choose the areas to audit, in case we are only interested in knowing some, also simulate the connection speed and choose the device (Mobile or desktop). Once configured to our liking, we will click on Run audits and the tool will show us its results reflected in metrics by areas.

However, there is also a that we can install it as a browser add-on and activate it by simply clicking on the lighthouse icon. However, this way it does not let us simulate the device and will always return results for the mobile version. With both options we can export the report or print it. The Add-on option also allows you to export the information in html and json.

Lighthouse Audit: Performance

Perhaps this is the most important module or area from an SEO point of view and I say this considering that there is a specific module called SEO, but its depth is of little value to a professional, since this area is based on their metrics into too basic items. A quick look at your SEO check list gives a good account of this:

The Performance module is already valuable in itself, because it tells us what parameters Google focuses on to assess a website at the . It is logical to intuit that these items will be the ones that Google’s algorithm incorporated to position a page within its results.

• FCP (First Contentful Paint): This is possibly the most important metric. It measures the time it takes for an element to appear on the screen to the user when they make the request in their browser and it is loaded in the DOM. The user perceives that the page is loading the content or images, or “doing something” and does not appear a blank screen that can cause bounce.
• speed index: The speed or indexing capacity of that url. It measures the capacity that the Google bot would have in indexing the content in its index depending on the code that it has to load. The greater the amount of html and the simplicity of the java and css processes, the greater the speed and ease of indexing.
• Time to Interactive: Metric that measures the time in which a user can interact or perform some action on the web.
• First Meaningful Paint: Metric that measures the time in which the first significant content (that is, content related to the user’s search) appears on the web.
• Firs CPU Idle: It is a metric that measures which elements of the web are interactive. Closely related to Time to Interactive, but based on the processes that can be executed when the web shows no interaction to load processes and respond immediately to user actions.
• Estimated Input Latency: measures the time in which a website responds to a user’s input or action and sets it at 50 milliseconds. All based on it (Response, Animation, Idle and Load)

Once these metrics have been taken care of and taking into account that it is almost impossible, as well as unnecessary, to optimize everything so that the scores are shown in green (the colors are those of the traffic light), we can move on to the Opportunities and Diagnostics part. Here Lighthouse tells us in detail what we can optimize to reduce web load times. It is a check list with a series of bullets that we already found in the Page Speed ​​Insight tool or in others external to Google such as GT Metrix or WebPageSpeed. We can summarize these optimizations in:

• Image optimization: reduce the size of images loaded on the page and postpone their loading
• Prioritize Resources: Generally external calls to resources that need to be prioritized or deferred and that reduce load time.
• Asynchronous loading: load the css and java code (whenever possible) after the html code.
• Minify java and css: reduce the java and css code to the minimum possible
• Set Cache: set a cache time for web resources and also enable cache comprehension
• Server response time: improves the speed of requests to the server. The famous Time to First Byte.

Lighthouse Audit: Accessibility

We now come to the area of ​​Accessibility, or what is the same, the metrics that are applied to weigh that a page meets the minimum requirements to be visible, understood and used by different users and by screen readers for people with limited accessibility. That is why fields such as: contrast, alternative texts in images, titles in labels, identification id, lists and tables readable by a screen reader, font type and size used, structured html content, etc. are measured here.

Best Practices according to Lighthouse

As a sign of Google’s goodwill and philosophy, Lithhouse also offers us a series of best practices to be able to implement them, if we don’t already have them, on our website. Among them is the use of the https or Http /2 protocol, geolocation is not requested when loading the page, javascript libraries are used,… It is almost impossible to comply with all of them, so it is not worth obsessing over this either. This module focuses above all on security when processing information and on not being intrusive towards the user.

Lighthouse Audit: SEO

As we have seen, it is based on a very basic check list of SEO elements. It is not very useful because it leaves out very important fields and because put that way, they would only serve you for a hypothetical SEO check based on a check list that we completely discourage, since it lacks a strategy and does not weigh the relevant factors for each page in concrete. However, it does give you valuable information if you have some “gross errors” from an SEO point of view.

Lighthouse Audit: Progressive Web App

If you have a site with this type of technology, it is undoubtedly a fundamental tool. Right now the use of this new generation of sites it has a minimal market penetration, but Google is pushing it, so we understand that several companies will soon develop this type of digital product and that Lighthouse will be one of the reference tools to validate it and know what to optimize.

Conclusions

As we have seen, Lighthouse is a great tool for auditing. As it is part of the Google ecosystem, it must be taken into consideration, yes or yes, since complying with Google standards is important to position your website in the search engine and because it also gives you clues as to what Google considers more or less important. We understand that the tool is in constant development and will include new indicators as technology changes. At the level of on-page SEO, it is still quite basic, although it can be used to check for bulk errors; but where it’s really fine and valuable is for WPO auditing and accessibility. Without a doubt, it should be a tool that you include among your usual ones, either for optimization, strategy or to know how your website is doing.

I hope you found this review of Lighthouse useful! If you think you can contribute something or have any questions, do not hesitate to write a comment.