Google recently introduced the large 300x600 half page ad layout. Previously, this layout was only available to the big players. But now google has made it available to all Adsense users with the limitation of only one 300x600 ad per page.Adsense 300x600 layout

Advantages of 300x600 half page ads.

It has always been a thumb rule for Adsense that bigger the ads, the better it will perform. The 300x600 ad being the biggest of all has the following advantages.

  • Big half page layout has more coverage, gets noticed better and result in more clicks.
  • More clicks mean more money.
  • Bigger ads also generally have higher RPMs (Rate per 1000 impressions) which again means more money.

Is it worth replacing your 300x250 or 336x280 Adsense ads?

Since Adsense imposes a limit of 3 ads per page, most of you would have to replace one of your ad units in order to accommodate the 300x600 ad. Although bigger, how a 300x600 ad unit will perform for your site depends a lot on your layout, content, ad placement etc. And the only way to find out is by trying out for a few days and analyzing the earnings.

300x250 vs 300x600 Performance Comparison.

So before jumping the ship, here's a review on how the 300x600 ad unit fared on Skipser. What I did was to replace a 300x250 ad on the sidebar with a 300x600 ad unit. Here's the Adsense performance report for the 300x250 ad unit.

With 94 clicks and a CPC (Cost per click) of $0.18 the earning was $16.48. The CTR (click through rate) was .28%. Now lets see how the 300x600 ad unit performed which replaced the 300x250 ad in its position.

Adsense performance 300x600 ad

As you can see, the CPC has dropped to $0.06. But the big increase in number of clicks more than compensated for the reduced CPC and the total earnings almost doubled. The RPM of the 300x600 ad unit is also almost 4 times that of the 300x250 ad.

Why 300x600 ad unit has less CPC?

There are multiple reasons why the 300x600 Adsense unit gives lesser CPC compared to it's smaller peers.

  • Being relatively new, fewer advertisers are using this ad unit. Chances of the ad showing charity (zero CPC) filler ads is higher. You will notice it yourself that Adsense occasionally fails to fill up the unit fully while showing text ads.Adsense 300x600 ad performanceUPDATE: Fill rates have changed a lot since the writing of this article. As more advertisers have started using this unit, adsense not able to fill the unit is really rare nowadays.
  • The 300x600 ad doesn't allow image-only ads. That means both text and image ads will be shown. The text ads are the same as those shown in a 300x250 ad unit, but the number of text ads needed to full the unit is almost double. Since ads compete against each other in terms of CPC, more number of ads mean lower CPC per text ad.
  • CPC of text ads usually turn out to be lower compared to image ads. Hence effective CPC would depend heavily on how many times Adsense shows an image ad instead of text.

Should you use 300x600 ad unit?

Clearly the extra clicks compensate for the reduced CPC and the total revenue is much higher. From the results above, the 300x600 ad unit is definitely worth a try. You would only gain much if not loose a little bit. Also, as the number of advertisers using this layout increases, the CPC would only improve.

So please try out and add your experience as comments below. It would really help a lot of other who are trying out like you.