Speed Index (Lighthouse)

Creating a fast website? Among other things, a low Speed Index is very important in this case. What is a Speed Index and why does it play a big role in your website? You can read about that here!

What is Speed Index?

Speed Index is a measurement tool for a Web site. It determines the load time of visible parts on the page. Lighthouse, Google’s open source tool, provides this and other metrics to measure and improve the performance of a Web site.(1)(2)

The importance of a low Speed Index

The metric Speed Index is one of 6 ways you measure a website’s performance. Speed Index measures the time it takes for the visible parts of a page to load. Lighthouse gives you insight into a page’s Speed Index: it calculates the visual progression between various frames. With Speed Index, the shorter the time, the better.

Speed Index is one of the metrics that carries the most weight, along with Time to Interactive (TTI) and First Contentful Paint (FCP). Among other things, Javascript is a possible reason that the load time for visible parts of a page is high. Loading unnecessary JavaScript files takes extra time.

The impact of Speed Index on SEO

The Speed Index certainly has an impact on the SEO of a website or page. Speed is an important factor in SEO and with improving the Speed Index, along with the TTI and FCP it is possible to optimize the website. One way to do this is with Lighthouse, the open source tool that offers these metrics. This will give you insight and opportunities to make certain changes.

My advice

We recommend using Lighthouse to gain insight into the Speed Index and other important issues that affect ranking in search results. Among other things in the use of Magento 2, Lighthouse is definitely recommended. A developer knows good solutions for improving scores, for example, through modifications in JavaScript.

The most complete book on website speed

I’ve written so much about speeding up websites and everything involved that I like to divide it into different sections; general, tools, speed improvement points and tips. Feel free to see and consult all the links below to learn more about tools and tips for speeding up your website.

General

• What is the website speed
• Website speed: The division between marketing and development
• The influence of SEO on UX
• The influence of web design on SEO
• SPAs and SEO
• What are the Google Core Web Vitals?

Tools

• Autoptimize
• Pagespeed.Compare
• W3 Total Cache
• Tools Pingdom
• Google Pagespeed Insights
• GTMetrix

Verbter points for speed

• First Contentful Paint (FCP)
• Time To First Byte (TTFB).
• Time To Interactive (TTI).
• Image for Largest view with content (LCP) preloaded
• Enable text compression
• Reduce the CSS
• Total Blocking Time (TBT).
• Reduce JavaScript
• Largest Contentful Paint
• Avoid an overly large DOM
• Delete unused CSS
• Remove unused JavaScript
• Deliver images in modern layouts
• Connect in advance to required origins
• Preventing obsolete JavaScript from being delivered to modern browsers
• Use an efficient cache policy for static items
• Remove duplicate modules from JavaScript
• Avoid multiple redirects
• Encode images efficiently
• Use lazy loading
• Load important requests in advance

General tips

• Tips for quickly loading a video
• Using Edge SEO for a faster website
• Installing a Content Delivery Network for SEO
• Optimizing images for SEO
• The influence of hosting on SEO