Tired of struggling?

Tired of your WordPress site dragging along like that little snail that poked its head out after the last rain?

A snail on a leaf.
This specimen has some strength, mind you.

I know what you mean. To fix this, you probably know WP Rocket. However, a newcomer has just arrived to help you get out of the doldrums. Its name? Jetpack Boost.

This young plugin – at the time of writing – has a very attractive promise: to improve the performance and the SEO of your site in a very simple way.

I don’t know about you, but I’m interested. I wanted to know more about it, so I put on my serial tester’s suit and tried out this new plugin.

Check out my detailed opinion and my conclusions without further delay.

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What is Jetpack Boost?

Jetpack Boost plugin to download on the WordPress official directory.

Jetpack Boost is a free plugin that allows, without touching the code, to optimize the loading speed of your WordPress site thanks to one-click optimizations that act on the CSS, JavaScript, and the delayed display of your images (lazy load).

At the time of writing this content, the plugin is only a few weeks old: its version 1.0 is available since April 2021.

The feedback from users is very good, for a plugin that “already” has more than 10,000 active installations.

Jetpack Boost has an overall rating of 4.5 out of 5 stars, although its reach needs to be measured (just over 10 people have left a review so far, which is not yet a large enough sample size).

Jetpack Boost = Jetpack… or not at all?

Behind the scenes, you should know that Jetpack Boost is developed and maintained by the creators of Jetpack, i.e. Automattic. The latter is the company that contributes the most to WordPress.

If Jetpack Boost is closely related to Jetpack, both plugins have their own way of working. This means that Jetpack Boost does not need Jetpack to work, and vice versa.

As the plugin’s FAQ on the official directory clearly details:

This is a separate plugin from Jetpack and it will always remain that way.

Nauris Pukis, an engineer at Automattic who works on Jetpack Boost, agreed in a post on the WP Tavern blog.

He stated, “We want Jetpack Boost to have a life of its own – focused on performance and make it available to everyone, including people who don’t want to use the main Jetpack plugin”.

Jetpack Boost and the Core Web Vitals concept

If Jetpack Boost promises to improve the performance of your site, it also puts the emphasis on two other elements, in terms of its communication, both on its description on the official directory, and on the presentation page dedicated to the plugin.

According to it, it would also be beneficial to improve your “Core Web Vitals” and, in turn, your SEO.

Don’t panic if this supposed gobbledygook still doesn’t mean much to you, I’ll explain it all to you. Let’s start with the “Core Web Vitals”.

These are a set of signals that Google considers important in evaluating the user experience of a web page.

At the time of publication of this article (August 2021), the Core Web Vitals focused on 3 elements:

  1. Loading speed, specifically the time it takes for a page to display its largest visible element. In the jargon, this is called Largest Contentful Paint (LCP).
  2. Interactivity, which measures the reactivity of a web page (e.g. the time elapsed between the moment a visitor clicks on a link and the page loads). Here, we speak of First Input Delay (FID).
  3. Visual stability (Cumulative Layout Shift, CLS). There should not be too many changes of elements on your page, as it loads.
Largest Contentful Paint (LCP), First Input Delay (FID) and Cumulative Layout Shift (CLS) are the three Core Web Vitals metrics.
Google indicates the good scores to obtain (in green) for its 3 Core Web Vitals.

Since June 2021, the Core Web Vitals are taken into account by Google’s algorithm, and deployed gradually until the end of August 2021 within an update called “Page Experience”.

In practical terms, this means that Core Web Vitals are now used by Google to rank a page in its search results.

However, as the French SEO specialist Olivier Andrieu argued on his blog, “the effects of this update will be very small on the results”.

In summary, don’t worry too much about the Core Web Vitals but take the opportunity to improve your page load time, which is very important for the user experience. For this, Jetpack Boost should give you a hand. 😉

What about SEO?

By improving the loading time of your pages, Jetpack Boost claims that you will also improve your SEO.

It is good to qualify this. If Google considers since 2010 that the loading time of its pages is a criterion of relevance for its algorithm, its impact is very small in terms of ranking.

By helping you speed up the loading time of your pages, let’s say that Jetpack Boost will indirectly help you not to penalize your SEO.

Man agrees with Jetpack Boost helping not to penalize your SEO.

If a page on your site is displayed faster, you are more likely to limit your bounce rate which is a bad signal sent to Google.

I hope that everything is clearer for you. Now, follow me: I’ll show you how to install Jetpack Boost.

How to install Jetpack Boost?

Jetpack Boost calls it a “simple installation process”. I’m spoiling, before I go on: indeed, everything is easy and happens in 2 steps.

Step 1: Install and activate the plugin

To start, go to the Plugins > Add New menu on your admin interface. Add and activate Jetpack Boost.

Installation and activation of the Jetpack Boost plugin from the WordPress admin.

Step 2: Link Jetpack Boost to a WordPress.com account

Now you need to link Jetpack Boost to a WordPress.com account to access performance scores and more.

Click on the green “Get Started” button:

Get started with the Jetpack Boost plugin.

I already have a WordPress.com account, so the connection happens automatically and quickly. If you don’t, the plugin will guide you through the creation process.

When all is done, you will have access to a brief settings page containing the performance score of your site, and 3 modules to activate/deactivate as you wish.

Find out more about them in the next part.

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How to configure Jetpack Boost?

A simple and clean interface

Jetpack Boost offers a clear and precise settings interface, mainly because its options are not numerous.

It can be divided into 3 parts:

  • An overall performance score(Overall score). This is a sort of average between your performance score on mobile and on desktop screens.

    For this, Jetpack Boost relies on scores from PageSpeed Insights, one of the performance measurement tools offered by Google.

    The plugin gives you a grade in the form of a letter. I get a C, which is still very average. So I have a lot of work to do, especially on the mobile version of my WordPress site!
Jetpack Boost overall score on mobile and desktop.
  • Three modules to improve performance. The user can activate/deactivate each module in one click, as it is already the case with Jetpack, for example.
    There is nothing else to configure, which makes life easier for the user.
The 3 modules of Jetpack Boost: Optimize CSS Loading, Defer Non-Essential Javascript, Lazy Image Loading.
  • Two stats on the impact of the loading speed. Here, we are only on the descriptive, it will not change anything to the behavior of your site.

    Jetpack Boost details, for example, that pages that take more than three seconds to load have a bounce rate four times higher than those that load in less than two seconds.
Jetpack Boost performance stats.

Now let’s take a look at the modules, which are the heart of this plugin.

Zoom in on each module

In order for Jetpack Boost to help you improve the loading time of your pages, you will need to activate one or more of its modules.

In detail, here is what they can do:

  • Optimize CSS Loading. This module uses a technique called Critical CSS. It consists in extracting the CSS code corresponding to the part of the site visible without scrolling (we say “above the fold”).
    This allows to display the page faster (no need to load the whole CSS file), especially on mobile.
  • Defer non-essential JavaScript. JavaScript code considered non-essential (especially from third-party scripts such as Google Analytics tracking code, for example) will be executed after the page has loaded, to improve display speed.
  • Lazy Image Loading. It allows images on your page to load only when the visitor scrolls down the page.
    Jetpack Boost says it “makes sites faster and saves bandwidth for your host and your customers”.

Each time you enable or disable a module, you can refresh the page by clicking on the small “Refresh” link, so Jetpack Boost calculates your new score.

Refresh the overall score on Jetpack Boost.

The plugin states that the results are instantaneous, which wasn’t really the case in my test. After refreshing the modules on JavaScript and Lazy load, the updated results took about 20 seconds to appear.

As for the refresh of the module dedicated to CSS loading optimization, Jetpack Boost specifies that it can “take longer”, “depending on the size of your site “.

With a stopwatch, it took 7 minutes for me to do this. That gave me time to sip a lemonade, at least…

To find out if Jetpack Boost has really boosted my page loading speed, I decided to run a series of tests.

Testing performance with Jetpack Boost

So, is Jetpack Boost really effective? You’ll have to wait a little longer to find out.

First, let’s recontextualize. For the purpose of this article, I have activated Jetpack Boost on my business website, which also serves as my lab. This site is hosted on a shared server of Bluehost (affiliate link).

It has about 15 pages and articles, and my Media Library contains 102 items.

Moreover, I use 29 plugins (26 of which are active at the time of the test) and the page builder Beaver Builder. So we are not on a fresh installation, as you can see.

Test with Pingdom Tools

First of all, I used Pingdom Tools, in order to have a global and general vision of the performance of my homepage.

Here are the results, before activating the Jetpack Boost modules:

Pingdom Tools performance test results, before activating the Jetpack Boost modules.

Once all three modules were activated, it looked like this:

Pingdom Tools performance test results, after activating the Jetpack Boost modules.

You can see a small improvement in performance between the two situations (before/after):

  • The loading time is almost the same.
  • The weight of the page has decreased, as well as the number of requests.

Testing with PageSpeed Insights

To get even more precise and specific results related to the Core Web Vitals, I then chose to use PageSpeed Insights.

This tool, offered by Google, provides detailed information about Core Web Vitals.

Here are the results without any of the Jetpack Boost modules activated, for the “desktop” version of my site:

PageSpeed Insights score before activating the Jetpack Boost modules.

And now look at what it looks like after activating all three Jetpack Boost modules:

PageSpeed Insights score with Jetpack Boost modules activated.

Again, we can see an improvement: the overall performance score went from 92 to 97.

If we go into the details of the Core Web Vitals, we can see that:

  • The Largest Contentful Paint has improved from 1.3s to 1.1s.
  • The Cumulative Layout Shift has gone from 0.002s to 0.003s.

Above all, all signals have turned green. It is not visible here, but I could also note an improvement of my score on mobile, from 58 to 68.

In conclusion, we can say that Jetpack Boost has had a positive impact on the performance of my site.

The above results give a first impression, but cannot be considered as a final judgment. You may have different data at home, depending on your host, or the plugins you use. While performance rating services are useful, you shouldn’t focus on that either, but rather on “the actual load time of your site” and “the impression of smoothness”.

Jetpack Boost and other performance plugins

For now, as you’ve seen, Jetpack Boost is an effective plugin but limited in terms of options.

The Automattic team knows this very well. On the official directory, they say they are “working hard to add new features and improvements to Jetpack Boost”.

It is therefore difficult to honestly compare it to other plugins on the market.

However, as a webmaster who wants to speed up the loading speed of your pages, you may want to know how Jetpack Boost compares to the competition.

There are several solutions to improve the performance of a site. For example, there are plugins to:

And then there are the cache plugins. The cache is a system that consists in keeping in memory the pages of your site already loaded, to be able to propose them to your visitors in a faster way, thereafter.

On the market, there are several competitors: W3 Total Cache, WP Super Cache, Comet Cache, or WP Rocket.

From the point of view of simplicity of use and options offered, WP Rocket (affiliate link) is the one that WPMarmite finds the most efficient.

WP Rocket homepage.

More than just a caching plugin, WP Rocket offers multiple options to boost your site’s performance:

  • Delayed loading of images and JavaScript.
  • HTML code minification.
  • Minification and concatenation of CSS and JavaScript files, etc.

In this respect, it is perhaps the plugin that is closest to what Jetpack Boost offers at the moment.

Between the two, WP Rocket is much more powerful, no hesitation there (however, it is not free and proposed from $49/year).

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But once again, I insist, the comparison is to be taken slightly.

Jetpack Boost may improve in a few months, because Automattic has the ambition to make its baby a real glutton. In any case, it is programmed to evolve.

As Pukis said at WP Tavern, “there’s so much that we want to do. Starting with simple modules that package up other typical optimization techniques (like concatenation, minification, maybe even photon?) – all the way to more advanced ideas like performance tracking, intelligent performance suggestions, etc.”

Jetpack Boost can work without worry with a cache extension. However, be careful: if the plugins you are using (the cache plugin and Jetpack Boost) have similar options, do not enable them at the same time. Jetpack Boost states that this could create “unexpected problems”.

Final opinion on Jetpack Boost

Throughout this article, you have been introduced to the Jetpack Boost plugin. Brand new to the circuit, it is interesting on several levels:

  • It fulfills its basic promise: to improve the performance of your website.
  • It is free (a premium version will probably be released in the future).
  • It is very easy to set up.

Download the Jetpack Boost plugin:

Its ease of use makes it the tool of choice for beginners who don’t want to get bogged down with technique.

And that’s a real asset because many plugins designed to improve performance are often complex to set up. Look at W3 Total Cache and its infinite settings page, and you’ll understand…

On the other hand, partly due to its young age, Jetpack Boost offers very few options at the moment. This is its main limitation in my opinion.

If you want an all-in-one plugin capable of optimizing your site’s loading speed from A to Z, WP Rocket (affiliate link) is for example much more appropriate at the time of writing these lines.

What do you think about Jetpack Boost? Give us your opinion by posting a comment right below. 👇