Website Loading Slowly? You Can Probably Blame Ads

Various things are to blame for slow loading websites. And ads are typically high on that list. Here's how to solve your website loading problems.

by Ryan Sullivan


| 11 min read

Few things are more frustrating than when you notice your website loading slowly. There are a myriad of factors that contribute to performance bottlenecks and slow page speeds, but one of the most notorious culprits that we’ve encountered recently is ad networks.

Ad networks have become the bane of the internet. It’s become enough of a problem that Google has started penalizing sites that go overboard with interstitial ads, or ads that try and trick users into downloading software.

We see ads causing performance issues on our client’s websites all the time. It’s true that you can make a decent amount of money from ad impressions, and for many publishers it’s their sole stream of revenue, but that doesn’t change the fact that poorly implemented ads, or ads that haven’t gone through quality control can cause serious performance issues that frustrate readers, and keep people from coming back to your website.

Browser window overloaded with ads

It seems like a joke, but this is not a joke.

There’s a virtual tightrope walk that constantly puts site owners in an awkward position. They’re always asking themselves, “How can I maximize ad revenue, and generate as many impressions as possible, without interfering with the experience of my readers?”

That’s not a fun place to be, so today I want to go over how you can figure out if ads are to blame for your slow loading website, why ads are a bottleneck at all, and what to do if you find yourself in a situation where ads are ruining your user experience and page load time.

Discover Why Your Website is Loading Slowly

The first thing we need to do is dig into why your website is loading slowly in the first place. We’re going to ignore things like subpar web hosting, bloated themes and plugins, database overhead, and things of that nature. Let’s take a look at ads specifically, and whether or not they’re contributing to your slow page load times.

I made this sweet video that walks through why ads are obliterating your page speed. This is a new feature we’re working on for Site Care, so I’d love to hear your thoughts on this whiteboard video. If you love them, we’ll keep making them ?

Testing Ad Impact With the Right Tool

There are a number of different tools that are used to test front end performance of your website. These tools are nice because they’re free to use, and simple to use as well. Just enter your site URL, wait a minute or two, and you’ll be given back loads of actionable data. Here are some of the most popular ones:

  • Pingdom Tools – Really fantastic interface, but doesn’t give back a lot of super technical data regarding performance bottlenecks. Also, limited locations for testing.
  • Page Speed Insights – This is the tool built by Google to let site owners know how the world’s biggest search engine sees their websites. This is a tool you’ll want to use pretty regularly if you’re focused on growing your organic traffic, since page speed is part of the search ranking algorithm.
  • WebPageTest – This is more or less the de facto standard for web performance geeks. The interface isn’t as pretty, but the data is second to none and overall this is an incredibly powerful tool.
  • GTMetrix – GTMetrix is similar to Pingdom Tools in a lot of ways, but has one silver bullet that neither Pingdom nor WebPageTest can provide. GTMetrix gives you the ability to enable an ad blocker in your testing so you can see true comparisons of how your site performs with ads enabled, and how it performs when they’re disabled. Note: The ad blocker integration is only available in the paid version, but well worth it for the value of the data you get back.

For today’s tests we’re going to focus primarily on GTMetrix and WebPageTest to show how ad networks impact your site performance.

 HTTP Requests

The most obvious impact of any ad implementation is the addition of HTTP requests. Typically speaking, a basic WordPress website will have anywhere from 30 to 150 HTTP requests. The WP Site Care homepage is pretty well-optimized, and we make 96 HTTP requests, so you have some context.

http-requestsAn HTTP request is basically just another name for every time your computer requests new information from your server, or any other server for that matter. Of course as more requests are made, that’s undoubtedly going to take longer to process. This gets even more complicated and involved when those servers are distributed throughout remote physical locations. Even though information travels at the speed of light, there’s still going to be latency if my computer is making hundreds of requests to Albany, Austin, Atlanta, and Acapulco all at the same time. Keeping HTTP requests as low as possible will ensure better performance for your website.

Now let’s take a look at an example from an unnamed website on the internet. The identity of the site owner has been removed to protect the innocent, etc. We captured the following results using the GTMetrix performance testing tool.

Screen Shot 2016-02-05 at 9.08.41 AMThe first screenshot shows the performance of the site with ads completely disabled. 81 requests is very respectable, as is a 2.8s page load time. Anything under 3 seconds is considered a win in most cases. The page size could be reduced some, but for an image rich website it’s not uncommon to have a page size around 2MB.

Screen Shot 2016-02-05 at 9.13.40 AMIn the second screenshot, ads were turned on. Here’s a percentage breakdown of the exact performance impact of ads on this website.

  • Page load time 8.6s – 307% increase in page load time when ads were introduced
  • Total Page size 3.55MB – 152% increase in page size when ads were introduced
  • Requests 446 – 550% increase in HTTP requests when ads were introduced

This isn’t even ad edge case or extreme example. We see and review sites just like this one every single day. We’ve seen sites where enabling ads introduced over 1,000 new HTTP requests!

Varying Physical Locations

The number of HTTP requests made by ad networks is a huge issue, and it’s compounded even more when you start to take into account where all of these ad servers are located. The more physical distance that has to be traveled to return ads to your website, the slower the page load times are going to be.

Let’s take a look at the same website from the last example, and take a look at how many different servers are being used to serve up this ad content.

Screen Shot 2016-02-05 at 9.01.02 AM

HTTP request breakdown for site not to be named

The pie chart on the left is completely out of control. HTTP requests are being made to over 150(!) servers across the world. It’s truly remarkable that data can be returned from that many places in less than 10 seconds.

The 15.7% slice of pie is the server that hosts the actual website. The WHOLE ENTIRE WEBSITE makes just barely more HTTP requests than the top ad network on the site. Let me reiterate that. One ad network makes almost as many HTTP requests as all of the content, images, and assets that make up this entire website.

Domain breakdown for

HTTP request breakdown for

Take a look at the HTTP request breakdown by domain for We load data from about 15 different servers instead of 150+. We could cut that number down even more, but we use the Twitter, Facebook, and Google APIs to add some features like our homepage twitter stream and things like that. It’s a conscious decision to include those additional HTTP requests, because they allow us to add cool features to our website.

We also know that massive entities rely on the Twitter, Facebook, and Google APIs a lot more than we do, so we can trust that they’re keeping their networks maintained and performant.

How to Keep Ads from Slowing Down Your Website

Now I’m not quite naive enough to say publishers should abandon the ad revenue model altogether. There are definitely other business models that can be more lucrative and have less impact on your readers, but when ads are the core piece of your revenue, it’s tough to make that switch without making some big strategical changes.

Know Your Ad Provider

We see a myriad of ad providers out on the web, many of whom are super reputable and keep their ad servers optimized, and require advertisers to comply with a strict set of guidelines.

Be aware of shady, but not this Shady. #dadjoke

Be aware of shady, but not this Shady. #dadjoke

The flip side is that we see just as many shady ad providers who are more interested in their own bottom line than they are about your website. They have loose or no performance guidelines at all. They don’t require asynchronous ad loading. They’re totally content with littering your site with garbage code, as long as it keeps their revenue numbers growing.

It’s completely common for these providers to blame any other myriad of factors for your slow performing website. But when presented with data like we’ve collected, it becomes almost impossible for them to refute. That doesn’t keep them from defending their poor implementation practices. If the “secret” about ad performance gets out into the wild, that could really damage their business. So it makes a lot more sense to keep things on the down-low.

Be Excruciatingly Picky About Your Ads

If you’ll be managing your own ads, be picky. Be extremely picky.

Low Quality Ad Networks are the Overnight Oats of the Internet

Overnight Oats are the Horrible Ad Networks of Your Daily Diet

There are a number of reputable ad networks out there. Here’s a list of some of the more popular ones, that for the most part, can be trusted to deliver quality ads in a performant way.

  • Google Adsense – This network is extremely popular as it’s extremely easy to optin, has few restrictions, and is very easy to implement.
  • WordAds – This is the network that runs ads across the entire platform. They’ve recently allowed publishers on self-hosted WordPress sites to apply.
  • – This network delivers ads primarily from the Yahoo/Bing network, which delivers ads at a very large scale. There’s also no minimum traffic requirement to join this network, so definitely worth checking out for smaller publishers.
  • RevenueHits – This is actually an advertiser that prides itself on performance, which is really rare in the ad network space. They also have massive inventory and no minimum traffic requirements.
  • Doubleclick for Publishers – This is another Google product, but it’s different than Adsense in that it’s the actual server platform itself, and then you ad inventory to it, from AdSense, third-party networks, and direct sell ads. There are some minimum requirements for using DFP, and to maximize revenue you will want to hire someone to set this up and manage it for you. From a performance standpoint, it’s as rock solid as they come.

Even this list of trusted sources can slip up from time to time, so if you’re not comfortable evaluating ads on a somewhat regular basis on your own, definitely reach out to professionals who can manage your ads and who can audit your ad setup from time to time.

Diversify Income Streams

The last option to help reduce the performance impact of ads on your website, is to start moving away from them. Or, at the very least, to start introducing new revenue streams to help subsidize what you’re earning from ads. Some really popular models that we’ve seen work well for our customers are

  • Affiliate Marketing – This is our favorite alternative to display advertising, as it’s still works 24/7, and it also makes the reading experience better for community. Affiliate marketing is using outbound links on your website with a built in referral code so you get a bonus if a reader purchases a service or product on another website
  • Digital Products – Create your own guide or handbook that brings a ton of value to your readers, and sell it for a small fee. You could publish your first book or release your first single if you’re a musician. You can start selling more easily than you think using GumRoad or a WordPress plugin like Easy Digital Downloads
  • Services – Do you have an awesome service that you can sell to your readership and community? It might be work looking at how to best provide that in a way that makes sense. It’s not quite as attractive because you end up trading time directly for money, but if it pays the bills, it’s definitely something to consider.

Just Say No to Slow Websites

I’d like to wrap this article up by challenging you to run your website through some of the tools I mentioned earlier. How do things look? Are ads killing your site? How many HTTP requests are coming from servers other than your own? If things look grim, it’s time to start putting together a plan for keeping those page load times in check.

Figuring out a way to increase your bottom line, expand your reach, and doing it all in a way that keeps your readers happy is definitely possible, but I’m not going to lie to you and tell you that it’s easy. It’s a lot of hard work!

If you’d like our team to do a quick analysis to see how display ads are impacting your site performance, hit us up in the comments and we’ll be more than happy to help out.

Ryan Sullivan | Vice President, Client Success


  • a
    amanda @runtothefinish 5 years ago

    OHHHH this is so timely!!! I know my ads are the issue each time I test site speed, so I’ve been trying to decide who to switch to because it’s too frustrating

  • Dave Warfel 5 years ago

    Really appreciate the list of ad networks that care about performance. I’ve been using AdSense (along with affiliate marketing) for almost two years, and in my experience, it doesn’t come with great performance.

    I need to run a test with AdSense disabled to confirm the true culprit, but past site speed tests elude to it being a big offender.

  • Tahir Taous 5 years ago

    My blog is new and I am not using any advertising network or any other plugin to increase page speed, what do you think should I start using any WordPress plugin to increase page load speed.

  • B
    Baljeet Kaur 5 years ago

    Is there any WordPress plugin to increase the speed of my website? My website is new and takes lot of loading time. Should I start using any WordPress plugin to increase page load speed?

  • M
    Michael A. Hunter 5 years ago

    Excellent post! My site is very slow. I have checked my site on Google Page Speed Insights and Gt-Matrix. My site page load speed is only 30/100 for mobile devices and 36/100 for the desktop. I have got frustrated. I will use your tips. Hope it will be ok. Your post is very helpful. I will come back to thank you if I could improve my site’s speed. Thanks!

  • A
    Ashley Melanson 4 years ago

    After some analysis, I’ve determined that ads are definitely slowing down our sites severely. However, I’m having trouble identifying which ad networks or ad tags are the biggest problems. Are there any tools you recommend for identifying this?

  • s
    slaystation 4 years ago


    Thanks for the list of ad providers and for the page speed testing tools.

    I’ve just started a gaming blog and I’ve set up a few amazon ads. I’m not entirely sure ads are to blame for the low speed. I’m sure the pictures play some part in it but I also suspect my hosting provider.

  • Adrienne 4 years ago

    As part of a website optimization team, I agree with everything you’ve put into this article. It is so important to analyze why a site is loading slowly because of the effect that will have on site visitors. No one wants to stay on a slow-loading page these days!

  • k
    ken 4 years ago

    nice article bro……could it be also caused by the theam installed on the wordpress?…please help me with possible solution as i have tried all i could.. thank you a await your respons

  • J
    Jaskaran Singh 4 years ago

    Very nice post but can you tell that is there any plugin for this which helps us in mantaining our website speed. Because wordpress provides lots of plugins for the optimization of the website like wp optimize or super cache etc. Can anyone help me?????????

    • V
      Vignesh 4 years ago


      Please check the p3 plugin from godaddy. Hopefully it helps.

  • Amber Bracegirdle 4 years ago

    Absolutely love this post. I’m a co-founder of Mediavine Publisher Network, and speed is one of our top priorities.

    This is why we only load the first two (maybe three, if the publisher chooses to run the optional leaderboard position) in first byte.

    They’re asynchronous. Everything else on the page is lazy loaded. That means it doesn’t exist until a reader scrolls near it, and won’t impact your site speed or your viewability score (important for ads).

    We’ve done some tests and found that running things this way means we can load up to 200% faster than our competitors. We’ve got a blog post about it, but I’m not going to be that weirdo posting links to our own site in a comment.

    It’s pretty nuts, but we’re obsessed with speed because we also run these ads on our own sites (we still own and operate three content driven websites to this day).

    Thank you for such a fantastic explanation as to why ads suck. We totally agree. We just try to make them suck less.

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    Alex Al-Mas'ri 4 years ago

    Hate to be that guy but one little math critique for an otherwise excellent bit of information. An increase from 2.33 MB to 3.55 MB is not an increase of 152%, it’s an increase of roughly 52%, or otherwise stated: with ads enabled, the number grew to 152% of what it was with ads blocked, which is probably what you were trying to say.

    I’m sure no one failed to get what you meant after thinking about it for a second or two, but it just looks better for the math to be accurately stated on a technical-kinda article. That’s all.

  • Zubair Akhtar 3 years ago

    Wow! this article cleared all my concepts about website loading speed specially about ads.

  • Don 3 years ago

    Hi, I just did a speed test on pingdom and found the Amazon affiliate ads are slowing things down, at least according to pingdom. However, if I understand this article correctly, affiliate ads are supposed to be a solution. Any suggestions are appreciated. I use siteground with cloudflare for CDN.

    Best regards,

  • Akinade Eniolabi 1 year ago

    Ads are a great nemesis for most sites but they are inevitable. Sometimes when I check my site through gtmetrix, I could see a number of redirects caused by AdSense ads which are slowing down my page rendering. If you use WordPress plugins like w3 total cache, it might help to cache some of the frequent requests made to your database so as to minimize http requests while loading your page. I also find the Minify function and object cache highly useful for a dynamic site.

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