No doubt AdSense is the best paying advertising platform for publishers but not everyone is making most of it. There are some reasons for low AdSense earnings other than optimization of the website that you will not actually think of. You can earn the best of CPC only when relevant adsense ads are served on your webpage. A couple of clicks on relevant ads can earn you more than a bunch of clicks on irrelevant adsense ads shown on the webpage. So, stop cursing yourself upon your failure in earning through AdSense now and start listening to me.
Among the reasons for showing less targeted adsense ads on your website, the following are the most common issues found and and can be fixed easily.
1. Google hasn’t crawled all of the pages of your website yet
This is one of the most possible reasons why irrelevant ads are shown on your webpage. When your webpage is new and not yet being crawled by the Google, you may face this issue. It may take up to 48 hours for Google to crawl your new pages. In the mean time, you would see some irrelevant adsense ads or slightly relevant adsense ads being shown on the webpage.
If your website or blog had pages that are quite old but not yet crawled and indexed by Google, try crawling them through ‘Fetch as Google’ option from webmaster tools.
Google crawler indexes pages by URLs. The same article or page with different URLs is indexed as many times as there are different URLs. The http://www.example.com is different from http://example.com in Google crawler’s perspective.
2. Google crawler can’t reach your site
If Google crawler can’t reach your site, how can it evaluate the content with the right ad to show on the ad space? It is easy to identify crawl errors by using webmaster tools.
You can access this feature named as ‘Crawl Errors’ that show all error URLs under ‘Crawl’ option set and resolve the issues.
3. Your site is restricted to access by robots.txt
Blogger or WordPress, your site uses robots.txt file. Robots.txt file is responsible for giving access to search engine bots to crawl your site content. Check your robots.txt file once and see if it has the following piece of text or not. If it doesn’t have it, add it.
4. Your pages need to be authorized
Just like other visitors, Google also cannot crawl your pages if they are login protected. Pages asking passwords to view information are not accessed by Google also.
You can give crawl access to password protected pages using webmaster tools. Once the access and authorization is provided, you would see relevant ads displaying on your login pages.
5. Your website is using session IDs in the URL
If your website is using session IDs on some pages, you may not receive targeted ads on those pages since the session ID therefore the URL changes time the page is loaded in browser.
So the URL cannot be indexed because of its dynamicity. The URL once loaded will not exist anymore.
In that case if you wanted such pages get indexed by search engines, remove dynamically changing session IDs from it. Then you will be able to see targeted as on that page.
6. You have placed Ad code in a frame
Another reason for showing irrelevant adsense ads on your webpage is because of using frames on your site. When crawling, if robots see your content and Ad units in two separate frames, they consider them separately as two different parts of the webpage. When there is no matching content on the Ad unit frame, the most irrelevant adsense ads are served obviously.
It is recommended to place ad unit on the same frame of the content in order to get served with targeted adsense ads.
7. Your page contains a refresh tag
If the header of your page contains a refresh tag (<meta http-equiv=”Refresh”>), this may also lead to your page displaying irrelevant. Removing this tag can help ensure that you receive targeted ads. Because Google robots are designed to think for humans.
8. Ad unit is placed in an iFrame
Placing AdSense ad units in iframes in not good. In fact, it is against AdSense program policies as there is chance of manipulating Ad code that may affect its behavior, targeting and delivery of ads on to the ad units that is strictly not permitted by Google.
If you are mourning over low earnings by placing ad units in iframes, remove them as soon as possible or else you will have to sob over your disabled AdSense account.
By the fact, Google doesn’t have that better technology to target ads on ad units placed in iframes. This is the major reason why Google take it seriously.
9. You modified your Ad code
I agree that you are smart enough to change Google Ad code to get highest CPC, but not as smart as Google. Google doesn’t allow modifying ad codes(except for smart sizing ad units, that too not the key elements in it but the responsive code).
If any such modification of ad code is found, the entire ad unit will show the alternate ad color that was selected while creating the ad unit.
10. Your website might not have enough content
This is one of the most cases of being shown the irrelevant ads. When Google crawlers don’t find enough content on the page, they can’t determine targeted ads on to the ad units. Google bots or any other search engine bots can only understand textual content and its meaning.
They cannot derive meaning from different media formats like of image, audio, video, macromedia flash and Java Applets. If any webpage was published with only multimedia content, the ads probably shown would be irrelevant.
To display relevant and targeted ads on the page add some sort of description of the media content or a couple of lines of textual information about it.
11. You site content doesn’t comply with AdSense policies
This is a sensitive reason for being shown irrelevant ads or not shown ads at all. If your webpage content doesn’t comply with AdSense program polices, Google technology may resist to show content on that webpage or might suspend your content until it is removed.
Don’t panic when you face this situation, find the content that violates AdSense polices, remove it and apply for reconsideration.
12. Your content is in unsupported language
Google AdSense program supports publishers blog in different languages. If your site’s language is not in that list, you are pissed off. Checkout the list of AdSense supporting languages.
It is recommended to remove Ad code on such unsupported language content pages until the issue is resolved.
13. Your Ad unit is set to display particular type of Adsense ads only
Choosing to display either textual or display ads but not both while creating an Ad unit is a cause for showing less targeted ads on the page. Either display or textual ads alone in an ad unit might have limited inventory and so when there are no relevant ads to display, irrelevant ads are opted in that format.
It is recommended to edit the preferences of your ad units to show both media and textual ads which in turn would increase your CPC too.
14. You have blocked too many advertisers
You may want to block some advertisers to show up ads on your website. It means your ad units are not available for those advertisers for bidding. Blocking ads from advertisers may be necessary but it should not lessen the value for our ad units.
Blocking too many advertisers would decrease demand for your ad units which in turn would lead to serving of cheap ads that are unworthy to display on your pages with beautiful content.
Update: Using HTTPS also delivers you irrelevant ads on your web pages.
These are the most possible cases for showing irrelevant, less targeted ads on your webpage. In most of the times, taking care of these 14 issues would help you get served relevant ads on your webpages. As discussed above relevant ads help you make best of the revenue from their respective ad units.