Reflections from the River

Singular Vs Plural Keywords: Does it Matter for SEO?

Key message: 42% of sites that appear in the top ten Google search results for the plural version of a keyword do not appear in the top ten for the singular keyword. For 14% of sites, their listing for the singular version of a keyword was over 20 places lower than for the plural version. Optimising for both singular and plural keywords DOES matter!

This is the first of 3 posts on the use of singular and plural keywords for search marketing. This post presents data on how searches for singular and plural keywords changes the top ten search results on Google. The second post explores search volumes for single and plural keywords. The third post estimates the potential value of optimising for both singular and plural keywords.

Knowing how to manage single and plural versions of keywords (e.g. bed and beds) is a significant issue for search marketing, if for no other reason that it potentially doubles the number of keywords being managed! It is, of course, possible that it doesn’t matter. Search engines are easily capable of returning search results for both the singular and plural keywords, regardless of which was used as the actual search term (see Google now uses stemming). The research reported below sets out to estimate how much the use of singular or plural keywords changes the search results returned by Google.

Research method

The singular and plural versions of 14 keywords were entered into Google.co.uk and the returned search results were analysed. The keywords selected were: bed(s), cabin bed(s), book(s), comic book(s), digital camera(s), best digital camera(s), laptop(s), acer laptop(s), lcd tv(s), plasma and lcd tv(s), mobile phone(s), business mobile phone(s), sock(s) and black sock(s) - to try to cover a number of shopping categories and both high and low search volumes. The searches were conducted using a Google Chrome browser in incognito mode. Following Robin Goad’s evidence-based conclusion that ‘plural terms are better at sending traffic to retailers than singular terms’ the plural version of keywords was used as the benchmark and the singular version compared to that benchmark. So, for example, a search was conducted for ‘beds’ and the domains in the top ten search results were recorded (e.g. www.bedroomworld.co.uk is in position 1). Then ‘bed’ was searched for and the first position of the domains found for ‘beds’ was located in the search results. If the domain did not appear in the first 100 results then its position was arbitrarily designated as 100 - note this underestimates how badly the worst performing sites were doing.

Results

Difference in SERP position for singular and plural keywords

This graph shows how many domains (out of 140) had exactly the same position for singular and plural keywords in the search results page (0 difference) and how many differed by 1 or 2 positions, 3 to 5 positions, 6 to 20 positions or more than 20 positions.  Whilst 44% of domains ranked equally well for singular and plural keywords (difference of 2 or less), 56% of domains ranked differently (difference of 3 or more).  59 out of the 140 (42%) domains that appeared in the top 10 search results for plural keywords did not appear in the top 10 for singular keywords.  20 out of the 140 (14%) domains appeared at least 20 places lower for singular keywords compared to plural keywords.

So, whilst search engines have the capability to return the same search results for singular and plural keywords, they have clearly chosen not to - a few domains that appear in the top 10 search results for plural keywords do not appear in the top 100 search results for singular keywords. The majority of domains (56%) rank differently (3 or more search results positions) for singular and plural keywords.

In the next post I will present results on search volumes for singular and plural keywords.