Continuing our series of frequently asked questions, this article looks at capitalisation with regards to SEO, common problems, and how the search engines handle capitalised keywords.
The specific question we were asked was "What impact do the use of capitals have on search engine results pages (SERPs), if any?"
This particular question is often asked in relation to town and location names, such as the English town of Reading in Berkshire, which can be swapped with the word ‘reading’. I will address this specific question to begin with before taking a broader look at capitalisation in Search.
All of the major search engines are case insensitive. That is to say whether you type [BOX], [Box] or [box] as a search query, it doesn’t matter, as you are more than likely to get the same results. So from an SEO point of view the best practice is to optimise your page so that it is grammatically correct, as you would any other typed document. As we always recommend you should write for the user and not search engine spiders.
One place where letters written in different cases can be an issue is within URLs, which are in fact case sensitive according to the HTTP specifications. Case sensitivity affects everything after the domain, which is case insensitive, i.e. whether you have http://www.example-url.com/ or http://www.Example-Url.com/ doesn’t really matter, as this is only used by DNS to find the web server address. What does matter is what you have after the domain, as different cases will indicate requests for different files. For example, http://www.example-url.com/Folder-Name/, http://www.example-url.com/FOLDER-NAME/ and http://www.example-url.com/folder-name/ are all different URLs and are treated as such by the search engines.
If all three versions of the above URL existed, it could lead to them being identified as duplicate content and there is a good chance that this will dilute the page’s link equity. For this reason, as well as to promote uniformity in order to make the process of creating URLs more straightforward, the recommended best practice here is to stick with lower case for all URLs. As an aside, lower case URLs are considered more aesthetically pleasing and are easier to read.
Case sensitive issues tend to arise if you use a server which is case insensitive, such as Microsoft IIS. With a Microsoft IIS server, the three URLs above would be treated as the same URL. Again the best practice here is to stick to using lower case in your URLs.
However, there are occasions when Google does return different results depending on the case used. This seems to be mainly where the letters could be either a word or an acronym. Compare [BAR],[bar] and [Bar] for example. The results produced are split into three sections, and it is in the third section where we found differences.
Differences were also seen when comparing results for [AND],[and] and [And].
Another oddity that came to light was seen when searching for [MAD] and [mad]. For [MAD] Google returns a currency exchange rate one box but not for [mad].
Therefore a best practice for including acronyms on a page is to include the full form with the acronym in brackets, at least in the first mention, as Google often highlights this in the search snippet.
Tags: best practice, canonical, duplicate content, Google, keywords, search, SEO, serps
Justin Sturges says:
April 14, 2010
As far as caps go in on page optimization they may have some value. In the original documentation for Google at Stanford they specifically state that capitals have some weight. Of course this just means that your key terms should be included in places where standard title capitals are appropriate. Just making the point that even though the command line is case insensitive doesn’t mean your pages should be!
Rik Stewart says:
April 15, 2010
Hi Justin, thanks for the comment. Documents are indeed indexed in a case sensitive manner, and our findings show that different results are shown for different capitalisations in certain cases, which sort of goes against Google’s official line of:
"Search is always case insensitive. Searching for [ new york times ] is the same as searching for [ New York Times ]." from http://www.google.com/support/websearch/bin/answer.py?hl=en&answer=134479
So as you say, making sure to correctly capitalise your documents is important for being found in search engines.
James Royal-Lawson says:
April 16, 2010
Did you do any testing to see if <acronym> and <abbr> tags still make no difference to SERPS? Google is constantly promoting the use of semantic mark-up and producing pages that help users – so of course we should be using those tags anyhow.
Agree that it would be a good best practice to write out phrases in full and place the acronyms and abbreviations in brackets for the first mention of that phrase (good writing standards anyway) but subsequent mentions of the acronym/abbreviation should make use of the <abbr> and <acronym> tags.
Rik Stewart says:
April 16, 2010
Hi James,
No didn’t look at the <acronym> and <abbr> tags, predominantly did tests from the point of view of a search user. Agree though it is something worth looking at.