How Fast is Divi Theme?

On August 18th Elegant themes announced an overhaul of the Divi Theme with the focus on speed. So how fast is Divi Theme in the wild?

Divi Theme in the Wild

We are managing a number of sites using Divi, and speed is a constant concern, requiring fairly complex combinations of plugins to achieve an acceptable level. So we thought we’d run some tests to see how well this update does in GT Metrix.

The first site is one of our own, chriswright.photography. We built this site eighteen months ago as a showcase for fine art photography. It’s heavy on images and relies on a combination of WPRocket, PerfMatters and OMGF to achieve an A rating in GTMetrix. It’s hosted at Siteground. Here is the report from GT Metrix.

You can see that TTFB (Time to first byte)was 618ms and the entire site took 1.4 seconds to load, deferring all images until the end. (See blank thumbnail at top left).

This arrangement worked pretty well, although there was some criticism of the user experience on mobile, it loaded reasonably fast.

Test Conditions

To test the latest update from Elegant Themes I disabled WPRocket, Perfmatters and OMGF, and enabled Cloudflare with the WPO plugin which gives me a simpler caching arrangement, serving content from the Cloudflare cache rather than Siteground. The aim is to bring down that TTFB figure.

Test Results

Well, the score is A which is a good achievement, although speed has dropped by 8 percentage points and unlike the first test, this hasn’t been achieved by deferring all images which makes for a much better user experience. There is some interesting variation here:

TTFB is 52ms down from 618ms – this is down to Cloudflare.

FCP is 378 ms down from 842ms

LCP is up to 1.3 seconds from 943ms

TTI is up to 1.1 sec from 924ms

FLT is down to 1.3 seconds from 1.4.

Recommendations

This is a major upgrade to the Divi Theme, involving some fairly complex re-engineering of core functionality. It has been delivered much faster than we had anticipated but has already been subject to a fix release.

For this reason, it’s unwise to simply press the upgrade button. This level of upgrade can be unpredictable in its impact on existing plugins. Which I should point out is not necessarily the fault of Elegant themes.

Here is a link to the Elegant Themes post – “Massive Divi Performance Update” in which they discuss, at a fairly high level, the changes that have been made. As you will see, they are deep and far reaching.

So, back up your website. If you don’t have one, create a staging environment and disable any performance enhancing plugins you have installed. Upgrade the staging environment and test all functionality, including editing pages.

If you’re still ok at this point, switch your plugins back on, one at a time, but disable any functionality that duplicates that provided in the Divi upgrade. That includes:

You can turn those back on one at a time to see if anything breaks.

Conclusion – How Fast is Divi Theme?

I think the broad conclusion is “Fast Enough”. The site, including images, comes in within Google’s current recommendations for site speed (Under 2 seconds).

It’s clear that the combination of Cloudflare and Divi is perfectly capable of delivering a fast site. Also clear that our WPRocket – Perfmatters – OMGF combination is faster, but in terms of human usability, not as good. Deferring image load is not ideal for a photography site.

We have done a lot of work improving performance to match Google’s Core Web Vitals metrics on websites with various themes and Divi was the one that we earmarked for migration. This upgrade means that we won’t have to prioritise migrating to a different theme for a while.

Divi is one of the most popular themes around but it still has some issues, notably that the builder is not integrated with Gutenberg so there will inevitably be a drag on performance. Having said that, this is a creditable effort from Elegant Themes and as far as we’re concerned we’re more relaxed about recommending Divi than we were.