Log in to your account at https://www.google.com/adsense
Click the Channels link below the AdSense Setup tab.
Choose the AdSense for content sub-tab and click the URL Channels link
Click Add new URL channel, and in the resulting text box, enter the URL that you would like to track.
Click Add channels.
The new URL channel will begin tracking data almost immediately.

Keep in mind that because URL channels don’t require changes to your code, there’s no need to designate a URL channel when generating your AdSense code. Once you’ve created a URL channel, it will track automatically.

You can use URL channels to track individual pages, or to track groups of pages based on the directory structure of your site.

To track a single page : enter the full path of the page in step 3 below:

Example : freeinfodownload.com/site_map.php

To track a script that generates multiple pages : enter the full path of the script, without the ‘?’, in step 3 below. This will track freeinfodownload.com/attorney.php?keyword=low cost attorney, freeinfodownload.com/attorney.php?keyword=two , etc.

Example : freeinfodownload.com/attorney.php

To track all pages below a specific directory : enter a partial URL in step 3 below.

Example : freeinfodownload.com/loan.html

To track only pages across a specific subdomain : enter the subdomain in step 3 below.

Example : sports.freeinfodownload.com

To track all pages on a domain: enter the domain name in step 3 below. To track all impressions and clicks across the domain (including any existing subdomains), enter the domain name without the ‘www’.

Example : freeinfodownload.com

1. After logging in, click on the link to ‘Advanced Reports’

2. Select the product you’re tracking: AdSense for content or AdSense for search.

3. Then click the radio button labeled Channel data.

4. Next choose the date range in which you’re interested.

5. Now choose the channels for which you’d like to assemble a report by using the check boxes.
According to the naming convention described in the custom channels section, if you wanted to find all of the channels associated with your home page, you’d type ‘Home’ in the ‘Find Channels’ box. Similarly, if you wanted to find all of the channels associated with rectangular ad boxes, you’d search for ‘Rect’. Once you’ve completed the search, you can simply select all of the results or choose them individually.

6. Once you’ve selected the desired channels, decide how you’d like to group the data.

A) For a day-by-day report of the data from the selected channels choose the Date radio button.

B) For an aggregate report of channel statistics over a selected date range, choose the Channels radio button.

7. Finally, click the Display Report button
Now You can understand which ad units are working for you and the getting most $$$

All The best… Happy AdSensing

Which ad units are the highest earners on my home page?
Leaderboard at the top of the page?
Rectangle in the middle of an article?
Skyscraper on the right side of the page?
Link unit under the left navigation?
Do my ads perform better with or without a border?
How does revenue for each of my AdSense for search boxes compare?
To get the most out of custom channels, it’s best to track every ad unit. This way you’ll have a core set of reports that you can use to aggregate data from all of your ad units, or to combine in different variations to gain deeper insight into your site’s AdSense performance and to answer the kinds of questions listed at the top of this section.

Creating Custom Channels

Understanding how you can use custom channels to answer the questions above will be essential in optimizing your AdSense ad unit performance. Let’s take a closer look in the following example.

Scenario: Nikhil owns a blog about medical information. His homepage currently has three ad units and one link unit, and Nikhil wants to find out which of the units is performing most effectively. To do so, he’ll create a separate custom channel for each of the four units to monitor their performance.

Creating and implementing custom channels requires a more involved process than that for URL channels. No worries – we’ll show you how to create custom channels in 4 easy steps:

Start off by logging in to your account and clicking the AdSense Setup tab, followed by the Channels link. For this scenario, we’ll be looking at AdSense for content custom channels, so make sure you’re on the right product and channel subtab. Then click the Add new custom channel

The next step is naming your channels.

It’s important to be precise and consistent when naming custom channels. The more information you provide in the name about where and how the ad unit is being used, the easier it will be to identify later, when you’re generating your channels reports. For the example used here, we suggest names like:

HomeTopLeaderMedicoCareEarth
HomeMidRectMedicoCareEarth
HomeRightSkyscpMedicoCareEarth
HomeLeftNavLinksMedicoCareEarth

You’ll notice that all of these names follow the pattern Page+Location+Ad Format+Color Palette. This is a pattern useful, but feel free to use whichever method works best for you.

Enter the channel names into the new channel box and click Add channels.

Now you can create your channel-specific ad code. Once your names are in place, click the AdSense Setup tab, then choose AdSense for content as the product.

Continue to choose the ad type, ad format, and color palette as you would normally, then in the Channels section,

select the name of the channel(s) you’d like to add by clicking the Add>> link (you can add up to 5),
and click Continue to see your choices reflected in the ad layout code.
Finally, you’ll copy-and-paste the code into your webpages. The channel identifier within your code will immediately begin tracking performance. If you already have ad code on these pages, you should replace it with the new channel-specific code.
Repeat the process for each of the ad units you’d like to track.