Testing the alt attribute

A French website (www.laboratoire-referencement.fr) very often tests differents attributes for Google, Bing and Yahoo to compare their effectiveness.

Let's see today their results for the alt attribute (the alt is used in images)

Aim of the test

The target of this test is to analyze if it is possible to rank a page on a specified keyword, only by using the alt attribute of an image. This test will be done through Yahoo, Google and Bing.

Procedure

A keyword (defined as KW) has been put in the alt attribute of an image such as

KW is a KeyWord which doesn't exist on any webpage known by Google, Bing and Yahoo.

NB: KW is not the true word used, it is kept secret in order to redo the test several times.

When we were looking for the keyword KW in theses 3 engines, the answer before the test was:

"No answer found" or No pages contain KW

If, after having indexed the test page containing the word KW in an alt attribute, a search engine, for the same query, gives as a result the test page, we can then come to the conclusion that:

(1) - The Alt attribute alone allows to rank a webpage with a given key sentence

If not, one can conclude that:

(2) - The Alt attribute alone cannot rank a webpage on a given key sentence

Limits

If we come to the second conclusion, it doesn't mean that the search engines never analyse the content of the alt attribute.

As a matter of fact, it is possible that:

• A keyword only in the alt attribute is not enough to rank a page on this keyword but brings anyway a bonus.
• This attribute is used to fight spam, over-optimization or duplicate contents.
• The test is not genuine for the word KW doen't exist anywhere else on the page.

Result of the test

The test page is not ranked if we make a query with KW on Yahoo nor Bing.

The test page is ranked with the word KW on Google.

Interesting, isn't it?