Breaking Down Page Speed Insights, Part 1: Performance
For the longest time, one of the biggest pushes in the web world has been towards responsive design and development. While this has led to a great number of advances, in both specs and tooling, it has also shone a light onto web site performance.
With the spread of hi-dpi, and more powerful devices over the last decade, more and more pages on the web are bloated – slowed down by unnecessary amounts of additional code and years of agencies selling the next big thing, adding snippets to your pages with wanton abandon.
However, more recently, this began to change, as Google started heavily pushing their Page Speed Insights. As more and more marketers, design leaders, and agencies became aware of the tool, it became the de-facto standard of testing page speed (along with tools like GTMetrix). Agencies and development shops were finally given the command from their clients – make my site do better.
But what is better?
In our first part we’ll take a look at the metric people tend to focus on the most currently: performance.
Let’s break down what affects your performance indicators, and why hitting 100% at all costs shouldn’t be your endgame, and why sometimes those 100% scores are not really fair.
Firstly, what constitutes your performance score, according to Google
First Contentful Paint (FCP)
The time it take for the first visible bit of actual content to render on page
Speed Index (SI)
The time it takes to render all the visible elements on the page (basically, the time it takes to render your “above the fold” content).
Largest Contentful Paint (LCP)
The time it takes for the largest amount of visible content (image or text block) to render and be fully interactive within the viewport (again, usually your “above the fold” content, but maybe only a hero image, for example)
Time to Interactive (TTI)
Lastly, something I’ve personally seen become more and more common, are developers using tactics to fake their way to 100%, just to hit that number. Look, hitting 100% is a goal everyone should strive for. Doing so by removing scripts when the page is hit by PSI is not the way to go. We should be educating clients on what those scores mean, and how different things can affect them in different ways.
