Find Which Plugins are Slowing Down your Site

A default installation of WordPress is very trim and will load pages very quickly. This is a purposeful decision of the development team, to keep the core quick and leave non-essential functions up to plugins, so that people who don’t need those functions aren’t slowed down by them.

With that said, most people will immediately start seeking to install some plugins once they install WordPress to get the functionality that they’re looking for. As you start building your site and tacking on plugins, you may not immediately realise the few milliseconds here and there that each plugin adds to your load time.

If you’ve decided that your page speed is getting a little slow (or if you haven’t even considered it), it may be worth doing a little audit to get an idea of which of your plugins are adding the most to your site load time. And in true WordPress style, there’s a plugin for that.

Install P3 Plugin Performance Profiler

P3 Plugin Performance Profiler is a plugin that you can activate just to do this audit and then deactivate it once you’ve finished tuning up your site, so that it’s not impacting your general site speed when you’re not using it.

Performing the scan

Once you’ve installed the plugin, you’ll find the plugin screen under the Tools menu. The user interface is very well laid out and easily navigated. To run your first assessment, hit the Start Scan button. Once you tell it to do an Auto Scan, it will then go through a process of loading a good number of your pages and assessing the load time of each one; this will take a couple of minutes, so be patient.

Understanding the results

Once the scan is over, you’ll be presented with an option to view the results of the scan. The results screen will look something like the image to the right. At the top, you get information about how many plugins you have, how long it took to load them all and what percentage of your page load speed is attributable to plugins. For me, it’s over 70%, so my site is now about 4 times slower than it was when it was first installed without any plugins. That’s not bad in and of itself – you have to balance functionality with page speed. But the really useful information comes in the breakdown.

The pie chart will give you a visual representation of the most burdensome plugins (each slice representing a percentage of the total plugin load time). In my case, the biggest culprits are Formidable Pro, OIOpublisher and WordPress Database Backup. This is where you need to make a decision as to whether the biggest offenders are really worth the extra load time, or whether there are suitable, more lean alternatives that will do the job just as well.

If you click over to the Detailed Breakdown tab, you can hover over each bar in the chart and see the actual load time for each plugin. The remaining tabs provide additional information about how each page that was scanned loaded, a comparison between the WP core load time, theme load time and total plugin load time, how many SQL queries were required to load each page and other metrics.

Time for a change?

Now that you’ve run the scan and seen the results for yourself, you’re in a good position to make an informed decision about what to do with your site. Review the heaviest plugins and decide whether you really need them. If you can’t live without them, maybe there’s a different, lighter plugin that will still achieve the same functionality? I’d be interested to hear whether your results made you take action.