5 min read

Your CMS Is Not An Ad Server - And How To Fix That

Chris Shuptrine
Chris Shuptrine
Updated on
April 6, 2019
Intro to Ad Serving

If you're new to ad serving, you're probably curious whether you can use your CMS (content management system) to display ads.

Not really. While there is some overlap between a CMS and an ad server, they are intended for different uses.

cms platform

What is a CMS designed for?

A CMS is designed to serve content that doesn't need to change with each request.

In other words, a CMS's information is meant to be relatively static. A news article or blog entry is put at the top of the page, and it's expected for everybody to see the same thing. That article is not supposed to change every time a browser reaches out to a server to fetch and render content.

In most cases, a CMS serves HTML pages and related content like images, HTML5 videos, etc, and it will have built-in tools that make it easy to manage the content. The big three — WordPress, Drupal, and Joomla — all do a great job at this.

But no CMS is specialized at serving ads, no matter if those ads are banners, native ads, or full-out sponsored content.

Why can't a CMS easily show ads?

Because ads have different requirements than static web content.


  1. Advertisers need to track metrics that most CMS won't offer: clicks, conversions, impressions for individual units on a page, viewable impressions, and so on
  2. Ads are tailored to the user. This could be through frequency capping (a user sees the ad only once per day), demographic data like age and gender, and/or past behavior information like what pages they've visited
  3. Ads involve revenue optimizations, such as if a publisher is selling their ad slots via auctions, whereby the ad server selects the ad that'll deliver the most money, a combination of relevancy, click-through-rates, and bids
  4. Ads involve pacing and capping tools, which influence the rotation of what gets displayed. A CMS doesn't have a decision engine that can decide what ad should show and when, so that the advertisers hit their daily/total spend goals

For instance, if you only had one advertiser, and they were appearing in the same spot to everyone, you could of course just use a CMS to insert this.

But simplicity isn’t the norm with advertising; most publishers want to increase revenue by selling to lots of advertisers, while also including complex targeting rules to maximize ad relevance and justify higher ad rates.

The ad decision engine, which is the key differentiator between a CMS and an ad server, is the tool that makes this happen. It ingests rules defined by the publisher (such as enabling 2nd-price auctions to increase CPMs) and advertiser needs (such as $5K spread evenly over a week), and then, out of 100s or even 5000s of ads, it chooses the right one to show in just milliseconds.

what is an ad server

What about CMS ad plugins?

Most add-ons that enable a CMS to serve ads (like WordPress plugins) are actually just ad servers by a different name. In general you have to sign up for the ad server separately, and then the plugin hooks into it.

For instance, a major WordPress ad server plugin is Ad Inserter. It's perfect if you have a low-traffic WordPress site. It has the most active installations of any WP ad server plugin and provides an easy way to manage direct deals and Google AdSense ads.

That said, plugins are limited in their ad server functionality.

These tools don't provide:

  1. APIs for updating campaigns or getting reporting automatically
  2. Server-side ad serving integrations for faster display times (they use page-slowing JavaScript tags)
  3. Ad format customization to show native advertisingunits, sponsored listings, e-mail ads, etc
  4. Revenue maximizing tools using 1st or 2nd price auction
  5. Mobile SDKs for showing ads within apps

While plugins will work for a vast majority of publishers who just need to hook into an ad network, any larger brand who wants ad customization and revenue scale would be better suited looking at other options.

What are my next steps?

If you're still unsure of what to do next, we are more than happy to set up a 15-min consultation to walk through your needs and discuss the best path forward. We wish you the best in your quest to launch an ad server!

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