In the WordPress world it’s common to hear that your theme should control the look & feel of your site and plugins should control the functionality.
That’s always been a best practice in WordPress. But it’s even more important when you start considering speed. You really want to make sure your theme is doing as little as possible outside of the look & feel.
With WordPress you have to use a theme. And then you add plugins on top of that. So think of the size of your theme as a baseline.
When you start considering themes you want to consider the number of requests (which is the number of files it has to load) & the total page size.
The easiest way to discover which theme works best for your site is to try out a few themes on your own site. Since WordPress has a such a clear separate between content & layout it will only take you a few minutes to test each theme.
Speed Test WordPress Themes
I tested one of the default themes, the Astra theme which I’ve used for over a year, and I wanted to test GeneratePress since I’ve seen numerous articles about how fast it is. As well as a theme I'll keep unnamed but it one of those bloated themes that includes tons of functionality.
I want to start by highlighting that the default themes like Twenty Twenty are actually pretty decent. If you wanted to use one of the default things it's pretty darn fast.
There are some bloated themes that have lots of functionality included that take 3 seconds longer to load, an extra MB of data, and dozens of extra files. I’ve kept this theme as “unnamed” because I don’t want to call out one theme in case they get better in the future. I do want to say this is one of the top-selling themes on ThemeForest and lots of people rave about this theme.
By switching from Twenty Twenty to Astra you save 0.1 MB. And you save a little another .05MB by using GeneratePress. So this means that they’re loading smaller files which of course speeds up the website for the end user.
Twenty Twenty & Astra has the same number of requests. GeneratePress saves 4 requests.
And in terms of the fully-loaded time it went from 5.8 seconds down to 4.1 seconds which is 1.7 seconds. And this is just from the theme.
So if you’re looking for really fast themes do a little research and you’ll find articles like these that help you decide on the top 2 or 3 themes. Then do your own testing.
Your theme is the baseline for your entire site. So it’s worth spending the time finding a fast theme that works for your industry. If you find the perfect theme and it’s 0.1 seconds slower than the fastest theme that’s probably fine. But if your site + theme is already slow and you haven't yet added plugins – then you definitely want to find a faster theme or maybe find a faster host.
Do make sure you aren’t installing one of those themes that adds 3 seconds to your load time. This is one of those situations where it’s more about not picking the wrong theme than picking the perfect theme.