You probably know that a website’s rapid load time is one of the essentials for good user experience and search engine optimization. You may have already heard something about boosting your page speed by using lazy load for images. But have you ever asked yourself how you could speed up your WordPress site if you did the same with your ads?

This tutorial will show you how to implement lazy loading for adverts and how it can affect revenues and page performance.


What is lazy loading?

Lazy load is a technique that defers the loading of an object until it appears in the visible area of your visitor’s browser. This feature is used by plugins like WP Rocket to implement images or videos on websites without ruining their page speed.

Advanced Ads Pro also provides a lazy load feature, but it’s not limited to images and videos only. You can use it for all kinds of injected content. The feature is available as an option in the settings of all ad placements.

Why should you defer (some) ad loading processes?

Why should you load single elements later than others? Lazy loading can help page speed optimization, save your visitors’ bandwidth, and improve the user experience. Since its effect is objectively measurable, search engines might also honor your improved page speed.

Ad networks like AdSense don’t load simple image files only when you inject their code. These ads call an external domain to load multiple files, perform checks, track impressions, and finally show the visible ad content on your website. This process repeats for every single ad unit.

load time with and without lazy loading
Page speed with disabled and enabled lazy loading

Some webmasters try to double their revenues by injecting more ads. In my experience, it’s not worth it. The visitor’s attention span is limited and won’t increase with a higher total amount of ads. The only thing that increases for sure is the load time of your website.

As you will see in the following example, a single AdSense unit increases the load time between 140ms and 200ms. Can you estimate what happens to your page speed if you’d inject a dozen of such ads into your site?

The effect of lazy loading on page load time and revenues

The following mini case study illustrates how the wise use of Lazy Loading can result in better performance and higher ad revenues. I already optimized my example page with the plugin WP Rocket before analyzing the lazy loading impact.

Two AdSense units are placed under the page header and at the bottom of each article. You can also see some affiliate links in the content area and several self-hosted image ads in the sidebar.

page speed optimization with deferred loaded ads

In the following, I will focus only on the AdSense unit at the post bottom because there wouldn’t be any advantage in enabling lazy loading for the header ad above the fold.

I used Pingdom to measure the page load time and ran a dozen tests for this case study. The average load time of the already optimized page was about 740ms. After enabling lazy load for the post bottom ad, it dropped below 540ms.

An improvement of 200 ms does not sound earth-shattering, but that’s a load time boost of more than 25%. I achieved it by just delaying one single ad unit. Keep in mind that the more ads you are injecting into your page, the higher the impact of lazy loading on the load time.

Lazy loading, ad revenues, and what you should pay attention to

Besides the positive effect on the page speed, I noticed better Active View rates of those blocks with the enabled lazy loading feature. This improvement can result in higher ad revenues for Active View campaigns in AdSense.

If you sell ads per impression, please pay attention to the fact that deferred loaded ads will get only tracked if displayed on the page. Very eager users who rarely reach the end of your articles won’t trigger such an impression. So you should expect a bit lower number of ad impressions when using lazy loading than you would estimate based on your traffic.

But that does not have to be a disadvantage. There is no better argument in the current debate about click fraud, bot traffic, and unreal viewability than using lazy load for ads and not selling bloated ad impressions.

How to enable lazy loading on your WordPress site

To use lazy loading for ads, you first need to install and activate Advanced Ads Pro. Afterward, you can enable this module in Advanced Ads > Settings > Pro.

Activate Advanced Ads lazy load
Lazy loading settings in Advanced Ads

When you enable the lazy load module, you can define when the ads should begin to load. Set the number of pixels before they are visible on the user’s screen. In the last step, activate the function for the placements you want to load your ads deferred. That’s it!

Advanced Ads Placement settings for lazy loading

Improving your page speed isn’t that hard. You can start enhancing your site with Advanced Ads Pro today!