I love AdSense custom channels. I create a new channel every time I generate an AdSense unit. On websites with multiple AdSense units, custom channels make it easy to see details about every ad placement including how many times people have viewed it, how many clicks it has received and the average earnings per click. However, if you aren’t opening your AdSense channels up for targeting by advertisers, you could be leaving extra money on the table.
Suppose you are an advertiser creating an AdWords campaign for a software program that runs only on Mac computers. You could create a campaign that targets many Mac-related keywords, but this might cause your advertisement to appear on many websites that occasionally post Mac-related news but are more frequently visited by owners of Windows-based PCs. Although you might get some ad clicks from these websites, your chance to successfully convert might improve if you focus your campaign on Mac-related websites. That’s what channel targeting is for.
With AdSense channel targeting, an advertiser can search for a specific website — or websites that are highly relevant for a specific set of keywords — and place a bid to have his advertisement displayed there instead of among the general pool of websites that may occasionally post keyword-relevant articles. For you, the publisher, this is a win-win situation; an advertiser believes that your website’s audience will be interested in his message, which may increase the number of clicks your AdSense units receive. If the advertiser’s bid is higher than the bids for the advertisements that AdSense would have selected for a unit, a visitor sees the targeted ad. If the advertiser’s bid is lower, a visitor sees the advertisement that AdSense selects from the general pool. Channel targeting can only improve the performance of your AdSense units; it can’t reduce performance.