So you joined Google AdSense, put a couple of ads on your site and then waited. And nothing happened. You check your reports a few weeks later and still nothing, maybe a few cents here and there. And then you tell all of your friends that Google AdSense doesn’t work.

The real truth is that your Google advertising may not be working because you aren’t using the correct size. That’s right, size really does matter. If you aren’t using the sizes that advertisers want, then you are decreasing your chances of good ad content.

Let’s understand the basics first.

Preferred Google Ad Sizes for Best Return

It turns out, Google has four basic ad sizes that they call “recommended” or “preferred.” If  you navigate to creating an ad in your Google AdSense account, you will see the recommended sizes listed at the top.

My Ads > Content > New Ad Unit

The preferred ad sizes include medium rectangle (300×250), large rectangle (336×280), leaderboard (728×90), and wide skyscraper (160×600).

You often see the medium and large rectangle within post content (like above) or on the sidebar. The leaderboard is generally the one you see at the top (or very bottom) of sites, and the wide skyscraper is the long ad you see running down the sidebar of some sites.

Why Does Google Recommend Ad Sizes?

You know how you go to a blog about food and all the Google ads are displaying something related to food, too? Well, advertisers “bid” on what they will pay for those contextual ads–or ads that are related to the content–that appear on your  (or other’s) sites. Like all of us, advertisers also want the most bang for their bucks and, for them, this often means the bigger, more noticeable ads.

Google recommends these ad sizes because those are the sizes that most advertisers show an interest. And, the more advertisers “fighting” (aka: “bidding”) for ads, the higher the price they will pay and the better for you from a revenue standpoint. So, if you’re using the ad sizes advertisers want, then it’s only natural that you see an increase in revenue.

Additionally, many advertisers are no longer choosing those 125×125 “buttons” that you put in your sidebar. If you have those displayed for Google AdSense on your site, take them off. My bet is that you aren’t making any money from them and they’re just taking up eyesore space anyway.