Page speed insight metrics: Everything you need to know

When it comes to lifting the lid and seeing how your website performs, page speed insights are a crucial part of technical SEO. As well as decreasing bounce rate, it also plays a huge part in whether a user will actively convert or not – often making the difference between a click-on or a box-off.

In this guide, we’ll lift the lid on all things page speed, giving you a handy rundown of the metrics you need to optimise your website for top-level performance.

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What tools and metrics do we need for page speed insights?

A Page Speed Insights report – which fits under ‘Lighthouse’, which is a handy dashboard that also considers other aspects such as UX – can calculate your overall website’s performance. This is viewed through the lens of Google.

The following section will handily break down what metrics and measures search engines actively look for when calculating your score, so you know which parts of your website could use a little tweaking.

Largest Contentful Paint (LCP)

The Largest Contentful Paint is one of the main metrics in the Google PageSpeed Insights report.

It measures how long your browser takes to populate and render the largest image or text block within its viewport, relative to when the page first started loading.

First Contentful Paint (FCP)

First Contentful Paint refers to the exact second that absolutely anything – and we mean anything – is rendered on your browser.

The term paint comes from the first load of a banner image or page background, which can help Google think you’ve got a fast-loading page.

Essentially, FCP is when the user can engage with – or benefit from – content.

Interactive to Next Paint (INP)

Time to Interactive is another crucial page speed insight, literally meaning ‘the time it takes for a web page to become fully interactive.’

Although the term ‘interactive’ can mean different things, Google officially defines Time To Interactive (TTI) with the following:

  • When the web page has successfully rendered and displayed content that’s useful to the reader
  • Event handlers have successfully been registered for the majority of visible page elements
  • The page now responds quickly and effectively to user interactions

Speed Index

Google defines the Speed Index of your site to be the amount of time that the content on your web page/site takes to become visually populated. Usually measured in seconds, when calculating the speed index of a webpage, Google marks the score against data harvested from the HTTP Archive.

Cumulative Layout Shift (CLS)

Cumulative Layout Shift is another crucial metric for improving user experience. It helps you measure visual stability by quantifying how often website visitors are faced with unexpected layout shifts.

After all, we’ve all experienced issues when the layout shifts unexpectedly. It can disrupt the user experience in many ways, from making them lose their place during reading to making them click the wrong link or button. This can sometimes do serious damage and contribute directly to bounce rates.

Obviously, a low CLS indicates that your page not only looks good but can be navigated even easier for users.

Total Blocking Time

Total Blocking Time (also characterised as TBT) measures the duration of the delay between user input and a direct web page response. Clicks, keyboard presses, and screen taps are all examples of user inputs and are measured in milliseconds before being integrated into the page speed metric report.

Total Blocking Time is calculated using the sum of all ‘Long Tasks’ between the points of First Contentful Paint and INP.

For your notes, any task that takes longer than 50ms is considered a ‘Long Task’, with the Total Blocking time calculated after this point. To make things easy, your dashboard is handily categorised in traffic light colours so you can see whether your site is fast, moderate, or slow – making immediate SEO action clear.

Final thoughts

Making sure you spend time actively improving your website’s page speed Insights metrics is a crucial task for any business worth its salt. When user experience comes first, your online presence is improved and deemed more useful by search engines – leading to boosted rankings and increased visibility in your SERP.

Essentially, if you’re aiming to bring organic traffic to your website and convert customers in a stacked online landscape then page speed insight metrics should be top of your checklist.

If you’re still feeling a little lost in regards to page speed, or you’ve never run one before, our technical SEO experts can help. We can also run full site audits and implement improvements, so your website is always operating at peak performance.

Sounds good? Get in touch today.

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