The optimal length of description and title tags

Posted by Sam Soltano on 9 February 2011 in News

Search engine optimization is quite a mysterious task, because nobody really knows how it works. There is absolutely no shortage of people writing about it, giving tons of advise, selling information and software packages that are supposed to "optimize your site". What remains mysterious is where all these people got their knowledge from, because there is very little first-hand information available directly from the search engines.

That is not to say that all this advise is nonsense. But a lot of it is based on nothing but anecdotal evidence, or even, actually, on nothing.

One of the subjects that is discussed to no end is the length of meta tags and we tried to apply a statistical approach here.

At W3Techs, we are permanently analyzing millions of web sites and we have good estimates of their performance. We used that information to look for a correlation between a websites traffic and the length of the meta tags. It turns out, there is a correlation.

Page Title

The page title (which is strictly speaking not a meta tag, but very often labeled as such), is certainly one of the more important elements of a web page. It is essential not only for SEO, but also for a good user experience when visiting the site. We have even defined a quality alert for pages without title.

In order to determine the best title length, we have classified all the websites into traffic rank categories and into title length categories (using the title on their home page). This gives us a matrix, which we can investigate to see if there are any dependencies.

The first thing we noted is, that missing page titles are much more common on sites with low traffic.

When we look at the length of the title, we see that very short titles and very long titles are more common on sites with low traffic, whereas on sites with high traffic medium sized titles are prevailing. When we take the size limits where these two trends change, then we get the range for the optimal length.

55% of the high traffic sites have a title length between 40 and 100, against only 40% of the low traffic sites.

The optimal page title length is 40 - 100 characters

There is one notable outlier in this correlation, which we eliminated in the diagram: Very established sites get away with extremely short titles, often only the site name. For example the title in Google.com is simply "Google". We presume these sites are so well known, that their names appear more often in searches than a description would. More people would search for "Wikipedia" than for "online encyclopedia". Although, that practice is not without risk, that much we have on good authority.

Description Tag

We applied the same technique for the description tag, and we get the same picture. We see that more of the high traffic sites skip the description meta tag than the title, but there is still a clear correlation between having a description and traffic.

Furthermore, low traffic sites tend to have too short or too long descriptions. The following diagram shows the limits for the middle range.

Share this page