Google Lighthouse

For example, the Lighthouse platform is already integrated with other Google performance analytics tools. B. Analytics for PageSpeed Insights and Browser-Based Monitoring with Chrome Browser Developer Tools.

What is Google Lighthouse?

Lighthouse helps you check if your site is working. Lighthouse 1.0 was originally developed as an audit tool for Progressive Web Applications (PWAs). Then version 2.0 also included SEO and performance analysis for regular websites. The third version, Lighthouse version 3.0, was released in early 2018 and had a new look and direct integration with the developer tools of the Google Chrome browser. Lighthouse remains an open source analytics platform that works at the URL level.

What checks can Google Lighthouse perform?

The audits that Lighthouse offers are divided into five optimization categories: Performance, Best Practices, Accessibility, SEO and Progressive Web Apps.

Users can select one, several, or all five categories, depending on which aspects of their website they want to analyze.

Performance

In this category, Lighthouse looks at how quickly a website or app loads and how quickly users can open or view content. Here, Lighthouse looks at six speed stats:

First meaningful display: This is the time before the first text or image is visible to users.
First Significant Paint – Indicates when the main content of the page becomes visible to users.
Speed Index: The Speed Index provides a constant measure of how fast content loads on a page.
Interactivity time: Specifies the time before the user can fully interact with the page and its content.
First CPU idle: The value in this category returns the time when the thread activity on the main page is low enough to allow the input to be processed.
Estimated entry delay. The above output is an estimate (in milliseconds) of how long the application should respond to user input during the maximum 5 second calculation window while loading the page. If the latency exceeds 50 ms, users may consider the application or website to be too slow.

Beacon performance analysis also includes recommendations for improvement. They offer many ways to reduce loading times, such as compressing images, cleaning up JavaScript or CSS, or reducing rendering-blocking resources such as JavaScript, external requests, or CSS commands. Properly implemented caching, server response times, and avoiding (or limiting) redirects are also recommended ways to improve site performance.

Beacon performance recommendations are as follows:

Reduce View Blocking Resources
Streaming of images in the latest generation formats
Enable text compression
Reset unused CSS
Make sure the text remains visible while the web fonts are loading.
Use an efficient caching policy for static resources
Improve Critical Rendering Path (CRP)
Avoid large images
Slow down the loading of off-screen images
Minify/Compress CSS
Minify/Compress JavaScript
Image optimization
Enable server pre-connection
Shorter server response time (time to first byte, TTFB)
Avoid diversions
keyword preloading
Use video formats for animated content
Decrease total byte weight
Avoid Excessive DOM Size
Measure performance with user timestamps and statistics
Reduce JavaScript startup time
Reduce the main thread payload

Recommendations

The 16 best practices reviewed by Lighthouse focus primarily on aspects of website security and modern web development standards. Lighthouse analyzes whether HTTPS and HTTP/2 are used, checks whether resources come from secure sources, and assesses the vulnerability of JavaScript libraries. Other best practices involve secure database connections and avoiding using insecure commands such as document.write() or enabling legacy APIs.

SEO

Lighthouse runs several tests to determine how well a website or app can be crawled by search engines and appear in search results. These Lighthouse tests, which Google calls SEO, are extremely limited. Anyone whose website or app does not reach the maximum score should make the necessary corrections. After making these changes, Search Engine Optimization has great potential for further improvements, which should definitely be explored.

Lighthouse is currently conducting 13 audits in the Search Engine Optimization category. This primarily relates to mobile or PWA compatibility, proper use of structured data and tags such as canonical characters, hreflangs, titles and meta descriptions, and page crawlability by search engine crawlers.

Accessibility

Lighthouse accessibility audits check how well people with disabilities can use a website or app. This includes checking key elements, such as buttons or links, to see if they have been properly described or alternative attributes assigned to images so that screen readers can describe the visual content as well.

Progressive web apps

This section was originally the core of Google Lighthouse, Progressive Web Apps Analytics, or PWA. Does the service agent register the site? Does it work offline with internet access? Does it give a 200 error? Lighthouse started with these audits, but now they are just one of five audit categories that really only matter to progressive web app vendors.

How do I access Google Lighthouse?

PageSpeed Insights – Previously, Google PageSpeed Insights only provided a score, but now this tool relies on Lighthouse's analytics capabilities. Each URL can be tested against six performance metrics and numerous additional checks and recommendations. The total speed value also consists of six performance measures. This will take you to PageSpeed Insights.
Chrome Browser Developer Tools: As of April 2018, Google Lighthouse will also be available through Google's Chrome Browser Developer Tools. Here, users can choose which of the five main categories to check out. There are also device options where users can choose between mobile or desktop, as well as a variety of simulated internet speeds that can be used for analysis. Finding Lighthouse Audits in Chrome DevTools.
Chrome plugin: A full Lighthouse audit can also be performed using the Chrome plugin. You can find the Lighthouse Chrome plugin here (if you're using the Chrome browser).
Lighthouse performance testing can also be performed through the Google web.dev portal. Here you will find the most important audits with all results and recommendations.

How can I view the entire website?

Lighthouse is a powerful website and PWA performance analysis tool. However, this tool has one major drawback: it can only work at the URL level.

Through the Lighthouse audit, Searchmetrics has developed a way to analyze entire domains and their respective online markets, determine how well the industry is optimized and how well a domain is performing against its competitors.