How to Optimise Core Web Vitals SEO

Core Web Vitals - Page Speed Optimization

Core Web Vitals SEO, Page Load Speed & UX

Page load speed contributes to good core web vitals SEO scores, but its usually more complicated than that. The old GTmetrix scores could be green A’s across the board, whilst Google’s Page Speed Insights remained in the 20’s.

From 21 May mid-June 2021 Google’s “core web vitals” will be incorporated into rankings calculations.

Two SEO factors that affect ranking performance on all websites are page load speed and user experience (UX). How to speed up website page load times became an important issue when Google began considering this aspect as part of the ranking processes. When they said “The web should be fast” they were not joking. On that basis alone, trimming bloatware from your WordPress and other CMS installations, and optimising images etc, makes a lot of sense!

Whilst it may only deliver a modest incremental improvement to rankings, reducing load time is definitely not the only reason for reduce page sizes. No one in the world likes slow-loading pages – yet in 2014, the average page size of the top 1000 websites had passed 1600k (1.6 Mb). By 2016, the average size was 2.3 Mb (*1) and in 2017 hit 3 Mb with many pages well in excess of that. A busy SEO company regularly encounter websites where the home page exceeds 20 Mb…

Such overly plump websites are somewhat painful to load on a mobile device on 3G or 4G networks! And for most sites, the highest percentage of visitors are using some type of mobile device.

For many small business sites, the goal should be page sizes under 1 Mb, and Google says aim for an above the fold load time of under 1 second.

Improved “above the fold load time” as well as overall page load time should positively impact visitor retention time, repeat visitor rate and, on e-commerce sites, be beneficial to revenue.

Revised:  Feb 2021

Core Web Vitals Optimisation: Costs

From: US$250 / NZ$340

This represents 5 plus hours of work, and includes:

  • image optimisation
  • implementation of premium caching plugin
  • testing and adjustments
  • theme tweaking as/if possible

How to Improve Core Web Vitals SEO Performance?

Optimizing core web vitals SEO encompasses multiple issues which must all be considered. When you start contemplating how to speed up website performance and page load speeds, here’s the sequence I suggest… *2

  1. Benchmarking – check your site on the testing services outlined below. Start here because it gives you the base points you need to to measure the impact of everything you do.
  2. Image Sizes – usually, this is the fastest way to make the most significant improvements. Make sure all images are sized correctly and compressed appropriately. When image pixel sizes (height and width) are specified, the text content flows around the image space before it loads. Use a “lazy load” plugin to only display images as they enter the viewport. Shortpixel is great for batch processing of all existing images, see details below.
  3. Caching – if you don’t already have caching installed, do so now. I’d recommend starting with WP Rocket Cache on a WordPress site because it is comparatively easy to use. From my own experience, it delivers better performance than it’s competitors. It also offers options to specify dimensions AND generate critical path CSS, all of which contributes to faster above the fold displays aka LCP (largest contextual paint) scores. “(*3)
  4. Home Page complexity – many sites open a multitude of recent posts, top 10 posts, posts from various categories, comments, featured pages and sundry other database-hungry content. Some lead-in to content sections is important for both visitors and search engine rankings… But remember that every element adds up in terms of total database requests and page sizes.
  5. Design Theme – when it becomes apparent that there’s nothing more you can do to improve performance AND the scores are still sub-optimal, you might need to consider changing your design theme! There are multiple themes to choose from that are built from the ground up with core web vitals firmly in mind.

Core Web Vitals SEO Performance Benchmarking

In order to determine the impact of incremental changes, one needs measuring tools. Whilst one test tool is ok, two or three is better. That is because whilst the results may vary between measuring services, consistency in upward or downward trends across multiple locations gives a far better picture. To that end, there are five services that I regularly use, as follows;

  1. Google Page Speed Insights: provides a good analysis on how Google rates the performance of a given page.
  2. Pingdom: offers website performance monitoring from 3 test site options; Amsterdam, New York or Dallas. Its fast, with succinct summary reports backed up by detailed waterfall data showing what portions of your site load slowly. See;
  3. GT Metrix: The free website speed analysis service tests access from several countries BUT you have to find and use the Legacy tests options or you pretty much see what Google’s PSI gives you:
  4. Dotcom Tools: Dotcom runs simultaneous website loading speed tests on 20+ test sites in multiple countries:
  5. WebPageTest – for NZ site owners, their closest test server is in Sydney;

Benchmark Website Performance

The process goes a lot more smoothly if you document what you are doing to optimize website performance and record the result each time you check page load time… In this case, I selected the Home page and an internal page to check website performance at each step.

You might opt to test more pages, and the default Blog page is a good choice because it generates additional database queries compared to a standard page.

Optimise Images – Size & Compression

Nothing cripples a site faster than loading your images straight from your camera to your website! Yet people do that, perhaps in the mistaken expectation that website software works like Facebook and automatically resizes all images to suit their use. Whilst Media settings and some themes do a lot in that direction, you’ve usually got to activate the settings correctly before you start…

Every image on the entire site should be optimised to improve website performance. Background images can be awfully big. Inserting 1920 x 1600 pixel images that are not compressed and that then end up “scaled to fit” is a good way to kill your website performance.

In most instances, JPG images offer the best performance and these should have:

  • Dimensions reduced to the maximum size that they will be displayed at
  • Compression by at least 10% – and in most cases over 30% which still offers good image quality
  • Their dimensions specified in the page/s within which they are displayed

How to Optimise Website Images

Where you see a recommendation in GT Metrix results relating to “optimise images” you should examine the list to see if there are any large ones that you can process.

Note: GT Metrix also includes more than helpful information – under each image that could be optimised, they give you a link to an optimised version of the file. That’s particularly useful for PNG files which are a little tricky to compress…

  • Click the “See optimised version” and it will open the compressed file in a new window
  • Right click on the image and choose “Save as” – amend the name to match the original
  • Use FTP to upload the optimised version to the correct location

Doing this one by one can burn up a lot of time, and there is an easier way!

Batch Processing Existing Images in Bulk

There are good plugins for automatically processing images across your website such as WP Smush and Imagify. My favourite is from the guys at Shortpixel – The default installation has limits on how many images that can be processed per month. Therefore I buy a 50,000 Image Plan for $30. You can also run the plugin on multiple sites and share that 50k image allocation across them!

Batch processing of existing images across the entire site is simple. Pre-set the plugin parameters for glossy or lossy and the maximum image size etc, and set it to work. There is an option to preserve copies of the original images. The thousands of thumbnails can also be processed.

Shortpixel makes short work of getting your image library under control!

Specify Image Dimensions: Also examine each image you have added on the page to see if any are being scaled to fit. In Firefox, right clicking an image shows such details;

image optimisation

Image that are being scaled can often be resized to the correct dimensions. This depends on how your design theme handles Featured Images, and what its default thumbnail settings are. Some design themes are not efficient at displaying Featured Images images. If there is are site-wide issues with images being scaled, you may need to consider a better design theme.

Most mobile-responsive design themes are engineered specifically to process images in a way that reduces page load times across all viewing devices. Featured images are displayed at full size on their respective posts Suitable small thumbnails are shown on Home page Recent Posts, and or in sidebars etc.

Improve Core Web Vitals with Caching

A paper written in 2010 showed clearly the benefits of caching on performance (*1). Caching on the measured sited saved 81 percent of the bytes, and 75 percent of the requests. The need to do increases with every increase to average page load size, and because Google is evaluating your site in new ways…

WordPress has several long-serving and respected caching plugins available at no cost. Perhaps the most well-known are the freebies;

  • W3 Total Cache
  • WP Super Cache
  • Quick Cache

I’ve used all three across many different websites over several years.

For all sites I manage now, I install the premium WP Rocket Cache plugin, and have an enterprise license for that purpose. It run on both Apache and Litespeed servers.

Plugins – Impact on Page Load Time

Plugins are not all created equal… Some of the oldest and most used plugins are horrendous at increasing page sizes and generating database requests. A number of plugins are so badly constructed that their resource usage impacts negatively on servers in shared hosting. Sometimes to the point where some hosting companies have banned them!

Certain types of plugins generate massive amounts of database queries. Broken link checkers, related content, external links managers and statistics generators feature highly on the list of rogue plugins… Each plugin has a measurable footprint on your page load times and inevitably on page sizes and requests. Tasks such as broken link checking and statistics are perhaps best done from external sources using freely available tools.

Alternatively, you should run your Link Checker, fix the errors and then deactivate it!

Two for One Plugins: In some cases, a plugin serves a dual purpose, allowing you to achieve a couple of desirable outcomes without increasing consumption of resources. An example might be a social widget that offers both Like buttons and links to your social media business pages.

  • Both All in One SEO Pack and Yoast SEO have an XML site map generator, eliminating the need for a separate plugin for that purpose.

I’ve tried Jetpack… I think it’s like a giant Swiss Army knife… does too many things, and weights a ton! Even when you’re not using any of the modules, it exceeds 300k and generates an awful lot of additional requests!

Related Posts plugins: these can be very server-intensive, and at the time of rewriting this I mainly use Contextual Related Posts.

Lite Plugins: The term “Lite” may not necessarily apply to the plugins feature set! Whilst it is often used to differentiate between the Free and Pro versions of a plugin, it is also used to describe footprint and resource usage… The differences between two plugins serving the same purpose can be quite extraordinary! By way of example, I spent an entire afternoon refining page load times for Related Posts and Social Media “Like” buttons.

Security Plugins

Some security plugins – such as Wordfence – include features that you don’t need to run all the time. Notably Live Traffic logging, and scans outside WordPress, image file scans and ultra-sensitive modes.

I prefer to use the the Block Bad Queries WAF, plus Block Bad Bots and Limit Login Attempts. This combination has a small footprint. I also use Reduce HTTP on many sites to further minimse unnecessary http requests.

Heartbeat Control

Any WordPress SEO specialist knows that WordPress itself has features that can slow your site down, notably the Heartbeat API which is capable of generating server CPU loads that slow things down significantly.

Note: read additional info on Security Plugins and Heartbeat Control here: –

Design Themes

These are not all created equal. Many themes are bloated to the point of obesity. Very few are designed from the ground up for load speed performance and SEO rankings… Be aware that if you want stellar performance, your current theme might be a liability and not an asset.

Some of the fastest themes available, according to multiple reviews, are as follows:

Home Page Complexity

Striking a balance between showcasing what your site offers and keeping the page size within sensible constraints is the challenge here. In your quest to determine how to speed up website performance, keep in mind that your Home page is the most important page in the entire site. Website speed optimization is crucial to keeping visitors there long enough to captivate their interest.

Sometimes less is more… Show them fewer choices in terms of recent posts, latest comments, slide shows, tags, categories and featured pages or posts, top post lists etc.

Hosting Location

Hosting location can make a significant difference to page load times. Does your website targets New Zealand clients? If so, it absolutely should be on EITHER on a server physically located in New Zealand OR running on Cloudflare.

Conversely, if you are a New Zealand business targeting clients in the USA, it would make perfect sense to have your site on a server in the USA! Doing so could reduce page load time by 5 seconds or more! That’s a dramatic improvement AND the hosting costs are likely to prove less expensive…

Example – This Site

This site is now housed on an A2Hosting server in the US, and runs on Cloudflare. It has been optimised with WP Rocket Cache and the Shortpixel image optimisation plugin. It has;

  • Approx 2 seconds in New Zealand, Australia, UK and USA etc.

Given that most of my clients are NZ, Australian & UK small businesses, the Cloudflare functionality makes perfect sense.

optimising page load speed

At the same time, Google’s Page Speed Insights score is far from perfect.

The Desktop score is better at 89. But no matter what I do, that’s as good as I could get it.

Design Theme Impact on CWV

My next step was to replace the website design theme with Generatepress – regarded as the fastest / best theme currently available for load speed optimisation. Theme replacements are not a 5 minute job, but the proof of the pudding is in the eating:

Summary of How to Speed up Website Performance

With some time and effort, your site’s core web vitals SEO and page load speeds can (in most cases) be dramatically improved. First check the current performance and then ensure that you are using the best caching option for your site. Next, evaluating plugin resource consumption and replacing greedy ones will trim resource consumption to the bare minimum.

Follow that by optimising image file sizes and specifying dimensions to get pages loading faster. Complete the process by looking closely at your Home page content. Consider your design theme… Ask yourself if its bloated code filled with functions you don’t use or need is an asset or a liability? Are rankings more important than fancy effects, slideshows and huge images?

As part of my SEO packages for small business, I take a close look at website performance metrics, and advise accordingly. If all of this is beyond your time resources or technical ability, please contact the best local SEO company for assistance.


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