How Many AdSense Ad Units Allowed on a Web Page

We all know that AdSense is to date the best contextual high-paying ad network.

AdSense has very strictly enforced program policies, and if they find that a website is in violation of their TOS, they disable the offending account.  It is very important to follow AdSense’s quality and program guidelines, in order to avoid having your AdSense account banned.

Google adsense

One of the most common questions any new blogger will ask is, “What is the maximum number of AdSense units I can put on a page?”

Google AdSense offers different types of ads, and most are categorized in the following formats:

• AdSense content unit
• AdSense link unit
• AdSense for search

AdSense used to offer AdSense video units as well, but they ultimately retired this option.
Here are the maximum AdSense ad units allowed for a web page:
AdSense content unit:

You can place a maximum of three content units.
Content units are available in following sizes:
728*90, 468*60, 234*60, 125*125, 120*600, 160*600, 180*150, 120*240, 200*200, 250*250, 300*250, 336*280

Personally, I have found 336*280 and 160*600 to be very effective.
You can use ads from multiple publisher IDs, but the total number of content display ads should not go beyond three.

Adsense link units:

AdSense link units perform really well when blended with your theme and placed above the fold. I tested this by placing it in the Navbar, and it turns out to be a top performing ad unit.
You can place a maximum of three link units on a page.
You can find the various sizes for AdSense link units here.

Adsense for search:

You can add up to two AdSense-for-search units on a page. For a big website, AdSense-for-search units perform really well.  If you have not yet set up AdSense-for-search units, you can read our guide on How to Set Up Adsense for Search.
You can read more about the maximum number of allowable AdSense ad units on the official blog post.  (Ignore the part of the post about the video ad as it is retired now.)
A few things which I have learned from my own experience:

Sometimes 2-ad units perform better than 3-ad units.
Placing ads above the fold yields better results.
A combination of image + text ads perform better.
There are many different options available for the placement of ads, but I highly recommend using a minimum of ad units, or utilizing adverts only at the bottom or at the sidebar.

Let us know how many  AdSense ad units you are using on your blog.  Are you using all possible ad units, or are you using fewer than the maximum limit?