Improving PrestaShop PageSpeed Score

Google PageSpeed is a free tool that helps you check your website’s performance. It provides an overall score and detailed analysis for each page you list to analyze, including suggestions for improving its speed. You can also use it to compare different versions of your pages or sites.

But what if PageSpeed reports a low score (especially for mobile devices)? Mobile Google PageSpeed score is significant because if users cannot access your store from mobile devices, they will leave your web page without reading or buying anything.

I helped hundreds of sites to improve PageSpeed score, and in this article will summarize 80% of causes and fixes to have a high score for your store.

PageSpeed Score on a Fresh PrestaShop v1.7 install

If you would test Google PageSpeed with a fresh install of PrestaShop v1.7, you should see something like 98 points for mobile (up to 100) and 99-100 points for desktop. If you see higher numbers – that means you have great hosting (you should be proud of it).

PageSpeed score on PrestaShop v1.7 is tremendous!
PageSpeed score on PrestaShop v1.7 is tremendous!

PageSpeed Score for a Fresh PrestaShop Older Versions

Older PrestaShop versions (v1.6 and lower) will report lower PageSpeed scores. Something like 74 points for mobile and 98 points for desktop.

The older PrestaShop version is typically slower because the PrestaShop Dev team does a great job of improving framework performance. Unfortunately, that is sad news for v1.6 store owners as there is a low chance to improve score without upgrading the PrestaShop.

PageSpeed score on PrestaShop v1.6 is not that great
PageSpeed score on PrestaShop v1.6 is not that great

The older version does not compress CSS and JavaScript files optimization. Also, images are not optimized. So a lower score is almost guaranteed.

Upgrade to the latest version as soon as possible.

I have checked some random PrestaShop site running v1.5, and I see the score is 61 points for mobile and 90 for desktop. That is not that bad, but since the PrestaShop version is ancient – it will take a lot of effort to improve the speed.

Random PrestaShop v1.5 store PageSpeed score
Random PrestaShop v1.5 store PageSpeed score

Is PrestaShop Hosting is Too Slow For PageSpeed Score

Hosting speed is one of the essential speed factors because every file you have on your store – should be downloaded to the users’ browser. This means if you are on slow hosting, everything will load slow – images, content, scripts, styles.

Hosting speed has its own metric called Time To First Byte (TTFB). Unfortunately, you won’t see that anymore in Google PageSpeed. But you can find this metric in a free GTmetrix tool.

If we analyzed the previous PrestaShop v1.5 site in GTmetrix, we would see that it suggests Reduce initial server response time. Unfortunately, that means server response time is slow, so no matter what will be improved in the PrestaShop store – it will report a great score because all content will load slowly.

But changing hosting is tricky and expensive in a time sense. So if your store has this problem – try to optimize other things first. That will be low-hanging fruit comparing to a hosting change.

Is PrestaShop Images Downgrading Google PageSpeed Score Too Much

Google PageSpeed can report you a suggestion serve images in next-gen formats – that most likely you are running an older PrestaShop version (I already wrote about it above), or your theme does not offer this option.

Images are the most significant cause to load site slowly. My suggestion would be to retest the page by switching to a default PrestaShop theme and testing speed. If the score difference is significant (more than 20 points), you have to do some tweaks to your theme.

If you see the Efficiently encode images suggestion, it is something that you can do yourself manually with free online image optimization tools. With this tool, optimize images and upload them to your store – enjoy a better PageSpeed score.

If you see the suggestion Properly size images, images are way too big in width and height. You can resize (lower width and height) with another free image resize tool.

Is PrestaShop Theme Not Suitable For PageSpeed

If you see suggestions Reduce unused JavaScript and/or Reduce unused CSS in your Google PageSpeed PrestaShop store report, then it is rarely something you can do about yourself. The theme might need customization to eliminate these errors, which is not worth the effort.

Leave these messages not optimized.

Is PrestaShop Caching Things Properly For PageSpeed

Suppose you see PageSpeed suggestion Serve static assets with an efficient cache policy. In that case, it means that your store is not configured correctly for image caching. So every time a user visits store pages – it will be re-downloading resources repeatedly, customing your server bandwidth, and having a slow user experience.

You can fix this issue manually yourself, but you would need to edit the .htaccess file. First – make a backup copy of that file because if you make any minor mistake – your entire store will not load until you fix it or restore to the previous .htaccess file.

In the mentioned file, locate the following code block:

<IfModule mod_expires.c>
ExpiresActive On
ExpiresByType image/gif  "access plus 1 month"
ExpiresByType image/jpeg "access plus 1 month"
ExpiresByType image/jpg "access plus 1 month"
ExpiresByType image/png "access plus 1 month"
ExpiresByType text/css "access plus 1 week"

// more lines can be here… 

And replace every time value (access plus 1 month, access plus 1 week and similar) to access plus 1 year. Save the file and check if your store is loading. If not – check if you closed quotes properly. If not – restore to the old .htaccess file.

Now check GTmetrix or Google PageSpeed score, and you will see increased speed!

Optimal PageSpeed Score For Your PrestaShop Store

Do not spend hours or days tweaking your store to get a 100 score for mobile and desktop. 100 score by itself won’t put your site to the 1st Google place, and Google said that page speed is not the ranking metric. If it would – then it would be easy to abuse.

Store speed affects user experience, and Google cares about this too much. However, many studies have shown that a slow site has a tremendous bounce rate (number of visitors leaving the site).

If you can have a 90+ score for Mobile and Desktop experience – that is great! If you can reach this number with just 2 hours of work – go for it.

If you run into an 80-90 score and take more than 2 hours to improve the score (see effort table below), it is not worth your time.

If your score is 60 or less – that is a red sign. Try to eliminate few performance issues to have a better score.

Effort to Fix PrestaShop PageSpeed

Here is some estimation for tweaks you can make for your store to load fast:

Description Effort To Fix Possible Score Improvement
Optimize images width and height Low Effort A lot (10-20 points sometimes)
Use new format images (webp) Medium Effort A lot (10-20 points sometimes)
Hosting change High Effort Average (10 points probably max)
Theme change Medium Effort Will vary from 1 to 30 points probably
Disabling stats plugins in the back office Low Effort Small score change (by 2-3 points)