Google AdSense can provide banners ads in eight standard sizes but if you are not too sure which of these sizes will perform best on your website, read this.
The graph below shows relative click rates (CTR) for all the standard banner ad sizes (relative to the classic "full banner") and as is obvious from the picture, the ad performance or click through rates are much better for larger ad units.
Best Performing Banner Ad Sizes
If you are using a medium 300x250 rectangle format on your site, it may be a good idea to do some split testing (for say a week) and then probably replace that unit with a large 336x280 rectangle. Similarly, try squeezing in a wide skyscraper in place of that 120x600 Skyscraper that you may be having on your site.
And while it is easy to include a 728x90 Leaderboard in almost every site design, make sure that it is not the first unit in your HTML source as it is not always the best performing unit.
Another interesting point here is that the 125x125 square ad format, which is now quite popular among the blogger community, seems to attract lower clicks than even the 468x60 banner of the "geocities era" so your advertisers may not be feeling very happy about this.
The AdSense support site also suggests something very similar:
The formats we’ve found to be the most effective are the 336x280 Large Rectangle, the 300x250 Medium Rectangle, and the 160x600 Wide Skyscraper.
Also, wider ad formats tend to outperform their taller counterparts, due to their reader-friendly format. The wider ad format also lessens the likelihood of readers leaving the ad unit altogether.
[*] The above chart was shared in an online webinar by the AdSense optimization team and you can download the full report from DoubleClick.com. Worth reading.
Find this article at: http://labnol.org/?p=11541
Reader Comments
The DoubleClick document referred by you for this chart is a very old document of 2006. From where did you dig it?
Written by jon on 12.08.09
I can’t figure which is half page ad…. I don’t seem to have it in my adsense account.
Written by imran on 12.08.09
Not too sure about this information because a totally different set of ads sizes works for me
I got one website where the 468×60 banner is always the top performer and i got the 120×90 by 4 link units that has always performed well on all my sites. I do have the 336×250 on one of my sites but the revenue from it is not very regular.
I do think it also depends a lot on which advertisers are targetting the format ( ad) that you have on your blog and how catchy thier ads are for it to perform on your blog.
For eg The banners i get on my blog link .com at the top right hand corner are always catchy ads and get a fair bit of traffic
Written by Jeff on 12.08.09
I have only recently come to realize that you can actually compromise CTR for CPC. My site earlier used to have a 336X280 banner at a prime spot.The CTR was good and CPC too was. But recently, replaced it with a leaderboard and see that while the CTR has dropped, CPC has become much more that overall revenues have increased.
Written by Anand Srinivasan on 12.08.09
What is the 300×600 size? Is this only available for premium publishers? I have not seen this in my account. Thanks
Written by Tinh on 12.09.09
@Tinh – The 300×600 display ad is currently not available in AdSense but you never know once DoubleClick is further integrated into AdWords .. Display advertising would be big.
@Anand – Here’s what the AdSense blog says on whether you should be using the 300×250 medium rectangle or the 336×280 large rectangle:
# The 336×280 large rectangle tends to have a higher clickthrough rate due to its larger size. It often performs well on text-heavy pages where it’s integrated into the content.
# The 300×250 medium rectangle is a widely supported format that advertisers often use when designing their branding and rich media campaigns. Using this ad format and opting in to both text and image ads may generate more placement targeting opportunities, which will help drive up competition for your ad space and should lead to higher earnings over time.
Written by Amit on 12.09.09
I am not sure but again either advt. size selection depends upon the template I select Or, I have to select a template to go for advt. sizes. But maybe what value is Traffic. And if traffic is present then only chances are better for an Advt. to be clicked no matter what the size is.
Written by HOBO(nickname) on 12.11.09
Amit, 300×250 is working fine for me. Google is also recommending to use large ad units.
Written by Anish K.S on 12.11.09
This is good for any adsense publisher. If you also give the overall percentage increase and decrease in CPM of adsense with the CTR on different ad unit. Then this will give us idea about how not to compromise between bigger ads and CPM. In my view smaller ads give less ctr but gives very high CPM hence overall increase in earnings.
This research is just slap bigger ads, Visitor surely noticed them and that why CTR is higher.
Written by RahulBuzz on 12.12.09