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Speed matters. But just how much does the perfect site speed score matter?

We’ve heard it many times: the loading speed of your website is critical to success, and has a direct impact on your SEO, discoverability, UX, CX, and even bottom line. But chasing speed can be a sisyphean task, and being able to find the right areas to put your energies into for the best outcomes can be more important than getting the perfect score. So how worth your time and effort is it, really?

Our Founder, Stewart Ritchie, explores the topic in depth.

I was recently asked an interesting question by a client: why should I care about my site delivering a load time which is milliseconds faster when internet speeds are so much greater today? Will it really make a difference?

I understand where this is coming from: in the age of widespread lower latency fiber networks and 5G, we expect that the speed problem has pretty much been solved. The reality, though, is that our expectations of speed have moved even faster over the last few years: our brains have collectively gone from accepting a loading time of a few seconds as completely normal to furiously checking our signal strength when staring at a white screen for more than a few milliseconds.

The improvement in connectivity speed has realistically only shifted the location of the speed problem’s bottleneck: instead of how long it takes for the data to get to your computer, the speed at which a device can process and render the data it downloads is the new problem area. And with such a variance of devices of different capabilities accessing the internet every day as more people come online, this is a significantly trickier problem to tackle. 

With better connections, then, the onus of catering for speed has therefore moved from the ISPs to us as site owners: ensuring our site delivers and can be rendered at speed on the widest possible range of devices is indeed absolutely critical

This is where Google’s Core Web Vitals sails into the picture.

Chasing the Core Web Vitals unicorn

With Core Web Vitals and the page experience project, Google is forcing all site owners’ attention to focus squarely on their own setups. As a set of data points which objectively measure a site’s load time, interactivity, and the stability of content as it loads based on how it achieves this across multiple devices across the world, Core Web Vitals is built to continuously shorten the gap from clicking to consuming, targeting the improvement of their (and your) results. The score itself is built from three main categories: Largest Contentful Paint, First Input Delay and Cumulative Layout Shift, to render a score out of a possible 100%.

Most importantly, Google uses the final score as a significant ranking metric. In a scenario where two sites offer the same content at the same level of quality, the Core Web Vitals score can easily be the tiebreaker which decides on the higher ranker, and can mean the whole difference in significant volumes of traffic to the sites in question. Less traffic means fewer clicks, engagement, and ads served!

This seems to imply that you should immediately drop everything and obsess over perfecting the Core Web Vitals score with priority. But 100% is a misleading target.

The vitals that matter more than others

Each of the CWV categories outlined are broken down further into measurement areas: however, not all of these are equally important towards the final score. In fact, the single biggest metric is Total Blocking Time (TBT), which measures the total time in milliseconds between the First Contentful Paint and Time To Interactive. 

On its own, TBT accounts for 30% of the weight of the global score, so if you had to pick a single item to focus upon, make this it. 

To reduce TBT effectively:

  • Run as little JavaScript as possible between the First Contentful Paint and the page’s Time To Interactive: look at that gap in detail and question the relevance of each line of code and whether it really needs to be there. 
  • Where possible, defer as much as you can to after the page has been interacted with: if certain functionality is not necessary for the first interaction, for example, push it for later. 

Small tweaks can and will make a major difference, particularly for mobile and older devices!

TBT is followed in weighting by Largest Contentful Paint (25%) and Cumulative Layout Shift (15%). Between them, these three metrics alone make up 70% of the score.

Don’t waste your time tackling your whole website

The Core Web Vitals score is calculated on a per-page basis depending on where your traffic goes to, not on your website as a whole. You can therefore waste a lot of time targeting a perfect score for the homepage, for example, with little to no impact on your score.

It’s therefore best to start from the pages which attract most traffic on a daily basis. This depends on your site’s nature and structure: if you’re a media outlet, your articles are probably the most important initial touchpoint, for example. Pick and choose wisely what to optimise: going for the highest-traffic pages will give you disproportionately positive results.

But then we come to the elephant in the room.

The problem with ads

Regardless of the ads you run, you get limited control over what ads load to your site. Today’s ads are complex monsters: .mp4s, HTML5 banners, .gifs.; these all have massive file sizes clamouring for loading space. They also come with baggage: trackers, identifiers, cookies, and the ad tech reading your visitor data, optimising which ads to serve, how to serve and load them: all while your own site is loading.

This makes ads the nemesis to a perfect Core Web Vitals score. But when your ads are central to your revenue, simply deprioritising them for the sake of speed and loading them later can be extremely tricky. If your ads aren’t showing up on time and correctly to the right audiences and generating results, you’re risking putting everything on the line for the sake of speed. So which do you choose: better speed and higher rankings, or lower speeds but higher ad revenues?

The answer lies in balance: spending time identifying the right balance for your specific business between readership traffic and your business needs is critical to getting this right. There’s no “one size fits all” solution here, but being very smart on what ads to load where and at which point during the process, and applying this with a targeted, well-thought out approach can make the whole difference. Clearly define your balanced boundaries between the perfect score and ad revenue, and target achieving the right trade-off in the long term.

You will never manage to solve the ad problem fully, and that’s okay. There are simply too many variables at play to make your ads work perfectly for your site speed, and that’s part of why chasing the ultimate CWV score can’t be your priority.

Care, but don’t obsess

I’ll say it as directly as possible: a perfect 100% score is, and will remain, unobtainable for most websites, and chasing it is a waste of time

  • You can very easily dedicate huge amounts of time, money and resources to doing so with disproportionate and consistently diminishing returns. 
  • It will also make ongoing work much harder to do, because the layers of optimisation you’ll have to put in place will make updating your site extremely tricky. Particularly for large organisations with multiple teams working across a constantly-updated website, this will be a deal-breaker.

The best solution is to aim for a good score instead. Define the right balance between how much resources you want to dedicate to keeping your CWV score healthy, put in processes which ensure you keep an eye on it, and target striking the right balance which works best for your organisation. Do care about keeping it healthy, but don’t obsess to the detriment of everything else!

Your website is constantly slowing down, so keep up!

Your site’s goalposts are always changing with each and every update, no matter how big or small. Even a website which remains exactly the same in every way will slow down over time.

This means optimisation isn’t a one-time thing, and you shouldn’t treat it as such. What is the ongoing work you’re doing to monitor your site’s speed and keep it optimised over time? What processes do you have in place specifically for your site speed targets? Define your balanced goals clearly, ensure you dedicate enough time and resources to it, and keep it moving.

However, don’t lose sleep over speed

There’s a lot to be said about site speed, and generalising an approach is next to impossible. However, the most important facts to keep in mind are:

  • Core Web Vitals are important. Do not ignore them, as they will only get more important over time. 
  • Don’t obsess too much over them either. The goal can’t be to achieve a 100% score, but to optimise where appropriate and useful to get the biggest gains.
  • Optimisation isn’t a one-off job. Clearly defining the right amount of resources you want to dedicate to it on an ongoing basis will ensure you stay on top.

One final tip: speed is very important to your site’s general well-being, but we’re sure you can define a whole list of “very important priorities” you have on your website to-do list. If your basics and processes are right, it is highly unlikely for speed to kill a website’s results. Strike the right balance for your organisation, and keep its position on your priority list as appropriate!

Stewart Ritchie Lead developer and founder of Powered By Coffee. Stewart has been building websites for 15 years and focusing on WordPress for 5. He founded Powered By Coffee in 2011 after finishing is masters degree. He lives in Guildford Surrey with his wife Sydney and their two cats.

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