When thinking about website monetization, Google Adsense is probably the first thing that came to the mind of many people. Created in 2004, Adsense is the easiest way to make money online. Making real money with Google Adsense is not as easy as it seems, but if Adsense wasn’t an efficient way to make money online, people would stop using it.
In this article, I’m going to show you 10 efficient tips to really make money with Adsense.

Understand on which sites Adsense works

Is it possible to really make money with Adsense? The answer is definitely yes. But not on all kind of sites. For example, I own a blog in French about visiting New York City (it is called Visiter New York) and Adsense works very well on it. On the other hand, my most popular site, Cats Who Code always had terrible results with Adsense, because tech-savy people will not (or less) click on Adsense ads.

One of the best Adsense tip I can give you is to know which niche are good and wich ones are to avoid.

Avoid “SmartPricing” like the plague

Smartpricing (which is everything but smart…) is when Google automatically gives the advertiser a discount based on the perceived value of your web site. Certain types of sites supposedly generate more sales so get a higher cost per click while others are typically more lookers and get paid less per click.

If Google placed your blog in the second category, no luck for you. In fact, for the same click on the same ad, a website can earn $1 while another will get on 10 cents!

In order to avoid getting “Smartpriced” by Google, you have to try to keep your CTR high. Low CTR sites (under 1 or 2%) generally ends up by being smartpriced.

Place Adsense ads on old posts only

In order to avoid smartpricing, a great idea is to display Adsense ads on old posts only. Why? Because the vast majority of your regular visitors don’t click on ads. By showing Adsense on old posts only, you’ll definitely keep your CTR high.

The following function have to be pasted in the functions.php file of your WordPress theme.

function is_old_post($post_id=null){
   $days = 15;
   global $wp_query;
   if(is_single() || is_page()) {
      if(!$post_id) {
         $post_id = $wp_query->post->ID;
      }
      $current_date = time();
      $offset = $days *60*60*24;
      $post_id = get_post($post_id);
      $post_date = mysql2date('U',$post_id->post_date);
      $cunning_math = $post_date + $offset;
      $test = $current_date - $cunning_math;
      if($test > 0){
         $return = true;
      }else{
         $return = false;
      }
   }else{
      $return = false;
   }
   return $return;
}

Once you successfully inserted the code into your function.php file, you are now ready to call the functions in your single.php template as shown below:

<?php if(is_old_post()){ ?>
INSERT AD CODE HERE
<?php } ?>

Identify high paying keywords

To appear on Adsense ads, advertisers have to bid on a specific keyword. Some keywords, such as “mortgage” have a way higher CPC than others.

A great way to maximize your Adsense income is to identify those high paying keywords and use them in your blog. Several lists of high paying keywords are available on the Internet, some are free and some aren’t.
A good list to start with is this one, which is completely free.

Work with keywords

Although you can’t directly control which Adsense ads appears on your site, you can work with keywords in the hope that Google will display related contextual ads.

For example, if you’re writing a post about Javascript, the keyword “javascript” has strong chances of being used in Adsense ads. If you want Adsense to display ads based on high paying keywords, you have to put these keywords on your document. Don’t abuse though; you may be penalized by Google.

To check your keyword density, here is a great tool : http://www.ranks.nl/tools/spider.html

Use section targeting

As I said before, in order to maximize your revenue you have to work on keywords. But what if Adsense is displaying ads based on a keyword you don’t want to be used? Using section targeting, you can emphasis some text as well as asking Adsense to ignore some other.

The following example shows how to use section targeting in your posts:

<!-- google_ad_section_start -->
    Content you want to emphasize.
<!-- google_ad_section_end -->

<!-- google_ad_section_start(weight=ignore) -->
    Content you want to be ignored by Adsense
<!-- google_ad_section_end -->

Display Adsense to search engine visitors only

Another way to avoid being smartpriced is definitely to display Adsense ads only to visitors who came from search engines.
The following WordPress hack will do that job perfectly. To apply it to your blog, insert the code below in your theme functions.php file.
Note that the $SE array is where you specify search engines. You can easily ad new search engines by adding new elements to the array.

function scratch99_fromasearchengine(){
  $ref = $_SERVER['HTTP_REFERER'];
  $SE = array('/search?', 'images.google.', 'web.info.com', 'search.', 'del.icio.us/search', 'soso.com', '/search/', '.yahoo.');
  foreach ($SE as $source) {
    if (strpos($ref,$source)!==false) return true;
  }
  return false;
}

Once done, open the file where you want to display the ads and paste the following code:

if (function_exists('scratch99_fromasearchengine')) {
  if (scratch99_fromasearchengine()) {
    INSERT YOUR CODE HERE
  }
}

Save the file, and you’re done. Thanks to Stephen Cronin for the hack!

Go Large!

Adsense ads can be displayed in various formats, but they don’t provide the same results. Although it depends of many factors such as your blog niche and layout, the large rectangle (336×280) has proven to be the best paying Adsense format. It is also one of the few Adsense block which can display video ads.

Use a personalized Google search engine on your blog

Many people don’t like the way WordPress search works, and I must admit that this is not the best feature of my favorite blogging engine. In order to have better search results for my readers, I decided to give a try to a Google custom search engine. You can try it, search form is located on my blog sidebar.

The tools works very well, and you can start monetizing it using Adsense. I found out that on Cats Who Blog, the search engine is very profitable. For those who’d like to learn how to add Google search to their blog, a very old post from Cats Who Code explains how to do it.

Don’t break Adsense terms of service

At last but not least, one of the best bits of advice I can give to anyone who’d like to make money online using Google Adsense is to be careful with the terms of service. For example, if you click on your own ads, or display incentive messages on your site, Google will quickly finds out and they will consenquently ban your site from Adsense.

You have to play by their rules, so don’t thing you are smarter than them. Respect the terms of services, optimize your ads using the tips I just gave you, and write great content so people will visit your site and click on your ads.