(Please note that since writing this article I have created a WordPress plugin that solves the problem of not being able to split test AdSense accurately and easily. You can find more information about this new plugin here: AdSense Split Tester WordPress Plugin.)

Today I am going to try and make sure you don’t make the same mistake I made which left easy money on the table – that could have been fixed overnight…

After making a few small changes to my Google AdSense Ad Units I was able to double my click through rate (CTR) for a consistent and fast improvement in income.

One of first things you are taught when creating a squeeze page or sales letter is to always test different versions of copy and formatting until you get a conversion rate you are proud of.  What I, like many, didn’t realize was that this should be applied to all forms of direct response marketing – AdSense included.

Just like how every market reacts differently to sales copy, people react differently to online advertising.  Using a template that provided a high CTR on your last site won’t necessarily produce the same results on the next.  It is crucial that you realise that there is no single best AdSense layout or theme that will work for every type of site or every market.

How to Optimise Your AdSense Layout

So how do you find the most optimised AdSense layout for your current site?  Easy!  Test it just like you would a squeeze page.

Many people get a bit anxious when it comes to performing testing on a web site but there is a way to achieve it without relying on installing complicated scripting. When testing, it is important to compare results against similar sets of data. Often people make a judgment on the effect of a change after just 1 or 2 days.  These 1 or 2 days might be different to other days though and this can skew the results.  A test on a weekend will also produce inconsistent results as the traffic on the weekend is different to the rest of the week.  It is less frequent and is usually made up of more casual surfers.  Dismissing a test on a Saturday because it produced fewer results than Friday may be misleading.

(You also have to be aware of holidays and other world or local events that may affect the traffic to your page.)

I find that across an entire week the traffic levels sit on average and the spikes cancel out any troughs.  1 week on most sites gets enough traffic and clicks to make an informed decision on the results of the test.

Note: testing a site that has low traffic may produce inconsistent results so I recommend getting at least 50-100 unique visitors to your site before doing significant testing.  A quick way to tell is if your CTR is consistent across the course of a week.

How to Test AdSense Layouts

The ideal way to test a page is to do an A-B split test.  This involves randomly sending a user to either version A of a page or version B.  Across a week the number of views of A and B will be approximately 50%.

For testing AdSense A-B testing can be difficult and time consuming to setup.  There is another approach though that will still produce accurate results…

Run an AdSense layout for an entire 7 days in format A and then another 7 days in format B.  After the 2 weeks is up compare the results and note the winner…pretty simple huh?  Just make sure you start and end on the same day each week and your traffic will be consistent enough to make the right decision.  At the end of each week make sure you document the number of impressions, click through rate, average cost per click and eCPM.

You can then repeat the process for a 3^rd, 4^th, n^th week continually trying to beat the best performer.   You will get an idea of what does and doesn’t work each time you make a drop or rise.  Once you start failing to beat the best performer you can set it up as your permanent AdSense layout for that site.  It isn’t unusual to double your CTR after just a few runs of testing.

What Layouts and Formats to Try

When you make your changes don’t be afraid to try drastic changes.  Just make sure you document the current format before you replace it – you can always go back then.

It is a common belief amongst marketers using AdSense that blended ads work best.  This isn’t always the case.  If you have ever tried Google AdWords on the Content Network you would know that image ads often get the highest CTR.  Image ads when done right can really pop out of the screen and make the user at least look at them…

Use this to your advantage and try it out on your AdSense site too.  What works for the advertiser will work for the publisher.  Image ads may have a lower cost per click than text ads but the increased CTR should make up for this.  When comparing a change, especially involving image ads, make sure you look at the eCPM as this will take into account the higher CTR and the lower CPC.

One of the biggest boosts I had to my AdWords Image campaigns was when I changed the images over to blue text with a red border around the ad unit.  You don’t have control over the image ads on your AdSense sites but this effect can be applied to text ad units too and is well worth a try.  Set the title to blue, everything else to black, and add a red border. This works because people associate blue underlined text with hyperlinks.  I have had great success with this format on some of my sites, but not all.

If you are still using the default ad unit then give blending a try.  Change the font type and size to the same as your main content and set the title colour to the same as your links; the rest of the text will be the same colour as your content; there will be no border.

Positioning can also change drastically between sites.  Some markets respond well to the large rectangle in the top left before any content; others are more interested in reading what you have to say so you need to capture their attention elsewhere.

To capture this attention put the ads inside the content.  That same rectangle placed one paragraph into the content can have an instant effect.

Read up on some of the usability sites to get an idea of how people are interacting with different styles of sites.  This article from Jakob Nielsen on Scrolling and Attention made me try adding an ad unit to the end of my content.  People are looking for the next place to go after reading an article so by getting an ad unit in their face at this time gives those options.  Remove any other useful links around the footer to improve it even further.

Sometimes removing a unit can also have a boost on your CTR.  Too many ads might be causing ad blindness on your site so by relocating or removing a skyscraper ad unit in the sidebar might keep them guessing.

Don’t be Afraid to Try

Optimising your AdSense layout has to be one of the easiest and quickest ways to boost your income so don’t be afraid to give it a go.  If you do it this way you don’t even have to touch any code – just make the changes in your AdSense account.

If you make sure you document everything carefully, the only risk is having a week of less than average income; just change it back after the 7 days if the results don’t improve.  I encourage you not to panic after one try though as the next change might be the big one…

It would be great to hear if you do give it a go and get some positive (or even negative) results.