Does URL Length Affect Ranking?

I was recently perusing results on the leading search engines, I seemed to notice that long URLs weren't very popular on the first couple pages for several keywords. That intrigued me, so I performed a true statistical analysis to see if my observation was merely a coincidence or a true correlation.

The methodology: I gathered the results of the queries that were naturally performed last month by myself and three associates using the two leading search engines and analyzed them. I counted the characters in the URL (including the http://) and tabulated the results against the ranking of the URL in the search results. The tabulated results were finally converted into a normalized "ranking correlation." The results for each of the two leading search engines were kept separate so that we could discover any differences between the two leading search engines for this factor.

The resulting graphs show the results for groupings of URL lengths normalized into a number between -100 and +100 showing the likelihood of being ranked higher/lower. A value of +100 shows that all 10 rankings were in the proper order to show that pages of the studied value ALWAYS rank HIGHER than pages of another value. A value of -100 shows that all 10 rankings were in the proper order to show that pages of the studied value ALWAYS rank LOWER than pages of another value. Numbers in between show the varying likelihood of rankings proportionally between - 100 and +100.

That is the number you see on the Y-axis. On the X-axis, we have the URL lengths starting with a grouping of URLs that were 11-20 characters long and continuing with each group of 10 URL lengths up until 61-70. Here are the graphs for the two leading search engines:

The URL lengths were grouped in this way in order to increase the number of data points available. Unfortunately it also reduces the precision of the results. It is possible to tell that URL lengths from 21- 30 rank much higher than URLs of lengths 61-70, but you are unable to see if URLs of a length of 22 rank differently than URLs of a length of 24 (for example). I did not list the grouping of URLs of a length of 1-10 because the number of data points were too small to accurately calculate a ranking correlation. I did not show any URLs longer than 70 characters for the same reason.

The result is very conclusive. Both leading search engines rank sites having URLs between 11 and 30 characters (inclusive) much higher than any other URL length studied!

Notes:

1. There was no exercise to attempt to isolate different keywords. I merely took a random sampling of the queries performed by myself and three associates during the month.

2. This is merely a correlation study, so it cannot be determined from this study whether the leading search engines purposefully entertain this factor or not. The actual factors used may be far distant from the factor we studied.

Jon Ricerca is one of the leading researchers and authors of the Search Engine Ranking Factor (SERF) reports at SearchEngineGeek.com. For access to the other SERF reports, please visit: http://www.SearchEngineGeek.com