As soon as you publish your site you should make sure that your site is as fast as possible. Slow sites may not necessarily make your SEO rankings drop, though from July 2018 on, it will be a small ranking factor (see More importantly though, if a visitor tries to access your site and it takes more than a few seconds to load the site, he might leave the site before it loads. This is registered as a bounce by Google, and will raise the bounce rate. A general rule of thumb is to keep the time needed to load your site under 2 seconds. There are a few websites that can measure the speed for you. Just a quick warning though: don't fuss too much about scoring points, keep in mind your users. As an example: a tool may give you points for having your Javascript files compressed or not. However, the tool may not look at the full size of the file, even if it is over 1MB, keep that in mind. Perceived loading time is the most crucial thing to optimize. Having said that, here are some excellent tools, and I will discuss all:

Usually, they will give you input about what's good and what isn't. You should be aiming at a score of roughly 80% or higher, and a load time of less than 2 seconds. All of these tools have their own particular issues they look at, and they don't give the same website the exact same ratings, but the trend is usually the same. Let me discuss some of the above-mentioned services:


I often use the GT-Metrix service, as it measures both Pagespeed and Y-slow in one session, giving you a nice overview of both:


GT-Metrix provides a lot of details of why a site runs slow, or general advice about this, split up in separate items. As you can see here, the Pagespeed and the Y-Slow scores are slightly different, though both A-scores. In this case, I know Y-Slow favors Content Delivery Networks more and gives you a lower score if you don't have one. That is only one of the examples why the score often differs slightly. One nice thing about GT-Metrix is that if it finds non-optimized images, it provides optimized versions if you click on the item. GT-Metrix also allows you to monitor one site over time if you register, reviewing it once a day.

Pingdom Tools

pingdom tools

Pingdom gives you pretty much the same information as GT-Metrix. Usually, it detects the site to load faster then the GT-Metrix site, which is why you should not trust this value too much. Instead, focus on the individual items found. The waterfall tab shows you how the individual resources of the site load, while the Performance grade tab shows you the items which cost you most.

Very nice with Pingdom is that if you register, you can monitor one site for free (forever, including uptime), with 5-minute intervals. This is very nice for monitoring changes you performed on the site or server upgrades:

pingdom tools monitoring

Google Pagespeed Insights

 google pagespeed insights

Google specifically encourages optimization of Above-the-fold content and visible content, which usually requires complicated tricks that are hard to achieve, like specifying CSS that only favors the above-the-fold content, where the rest of the CSS should only be loaded later. Therefore, it is very hard to get a score over 95 here, but that should not worry you too much, hardly any site does. JCH-Optimize has an Optimize CSS Delivery feature that aims to achieve this, you might give this a try, but make sure to check your site remains functioning correctly then.


A nice newcomer is DareBoost. It measures the main aspects of speed and performance, but it also throws in a few security and SEO checks. It is available in a free and some paid packages, but the free checks are already quite nice:


Yellow Lab Tools

Yellow Lab Tools is actually a tool developed for front-end developers. Of course, it checks the general issues like caching, javascript and CSS optimization, etcetera, but it also checks your resources a bit deeper. As an example, it checks your CSS for efficiency, so if you use the full Bootstrap CSS files, but you only use basic stuff and no tabs or sliders, it penalizes you for having included that CSS for nothing. Especially if you build your own templates, this is a very useful tool. If you use commercial templates, you may not get the perfect scores. This is why only has a B score here, as opposed to the 100% in Pingdom and Pagespeed (due to the full Rockettheme CSS I use):

 yellow lab tools

Load Impact

A tool with a different approach is It does not just look at a single session, but it fires a load of dummy traffic with Virtual Units to your site and measures how your site can deal with that. Especially if your site is popular with many visitors, this might be a very useful thing to test. Loadimpact is a paid tool, but it allows you to run 5 tests of 5 minutes for free every month:

loadimpact test


Fortunately, for most issues there is a solution, either within the Joomla core (like caching or Gzip) or using an extension. So in the examples above, most issues have been solved, and while for other issues, there is still room for some improvement. Note that these tools only give general advice, you should also use your own common sense. As an example: If your site loads a dozen full-screen images, the tool might tell you that the actual individual images are fully optimized, but it will not tell you that you're quite foolish, loading these super large images.... As a consequence, you could have really high scores with a slow site.... My own site is a bit of an example: My GT-Metrix scores are 99 and 99, but I had to use local @fontface fonts to achieve that. A single call to Google fonts could possibly be quicker, but I have no control over the caching-lifetime, since the font is on the Google servers, lowering my scores.

Also, while some tools have different priorities, a combination of tools plus your own common sense usually works best.

Run a Full Website Scan in Minutes is fully built and written by Simon Kloostra, Joomla SEO Specialist and Webdesigner from the Netherlands. I have also published the Joomla 3 SEO & Performance SEO book. Next to that I also sometimes blog for companies like OStraining, TemplateMonster, SEMrush and others. On the monthly Joomla Community Magazine I have also published a few articles. is not affiliated with or endorsed by The Joomla! Project™. Use of the Joomla!® name, symbol, logo and related trademarks is permitted under a limited license granted by Open Source Matters, Inc.
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