If you have less than 1,000,000 monthly pageviews, the answer may be “No, you don’t”. In that situation, you might just want to use AdSense.
You do need an ad server when you want to run two different ads in the same space.
This may happen for a couple of different reasons:
You are approached by an advertiser for a direct deal
Normally a direct deal will require a specific number of impressions to be delivered in a certain timeframe. There may also be additional constraints, such as targeting users from a specific country or region, or only targeting specific device types. An ad server handles all of this for you. There are certainly other ways to make this happen, but it’s literally what ad servers are made for. The deal may be structured like this:
- 500,000 impressions
- Run of Site
- 728×90 and 300×250
- Flight Dates: April 1 – May 30th
You need to run a Sponsored Post
You may be approached by an advertiser who wants to run their ads on a single page of your website, but not the entire thing. A common example is the “homepage takeover”. Setup properly, an ad server can help you do this.
What ad server is best?
DFP Small Business is the best choice for most websites. It has really good controls, really good reporting and is highly customizable. It’s also free, when you sign up for AdSense (also free). There are a few other capable options, but DFP SB is our default.
Should you self-host?
Probably not! Because there are top-notch hosted alternatives available for free, there’s almost no reason to self-host your ad server anymore. The risks are not worth it. Fast ad serving requires fast hardware. Why pay for it when you can get it for free? Also, why take the risk of getting hacked? The only reason to consider self-hosting is if you’re just really interested in how ad server software works.