When analyzing my Google Adsense performance, my Adsense performance reports clearly indicated which ad size, ad unit, ad type, and design were performing best and increasing my Adsense earnings. Below are my findings.
In my experience running ads using Adsense for ten years, the following Adsense ad sizes or link units performed best:
336×280 Large Rectangle
160×600 Wide Skyscraper
The following ad sizes or ad units did not perform well:
468×15 Link Unit
200×90 Link Unit
120×90 Link Unit
160×90 Link Unit
Profitable ad types and units
Text ads and static images created the most cash flow whereas Animated Images, Rich Media, or Flash ads did not receive as many traffic clicks.
Popular ad design clicks
In looking at Adsense text ads, and at my top performing sites and pages, I noticed that several sites that have ads with the vivid color difference on the site URL are clicked more frequently. As an example, on one of my top performing sites, The URL color is vivid red and it’s the only uniquely brightly lit red item on the page layout.
Best Place for Adsense ads
Taking into consideration Google’s 2012 Panda layout algorithms, more than three ads on one side of the page can hurt your website ranking. Use only one or two ads above the fold. This gives the page layout a user friendly feel, as opposed to a MFA (Made For Adsense) site.
The best performing placement for an ad is at the bottom of the content.