Dave ChaffeyAn n-gram is a phrase made of n-words: a 1-gram is a single word, a 2-gram is a phrase made of two words, and so on. Within search marketing, they are used to assess the number of instances of a keyword or keyphrase within a set of keywords.
For example, if analysing laser eye treatment-related keywords, we could assess the number of times a 1-gram keyword like laser, eye, treatment or surgery occurs. We could then assess the number of times a 2-gram or 3-gram occurs, for example, ‘laser eye surgery’ or ‘laser eye treatment’.
Using this approach helps us see the relative number of keywords that occur across all search terms. In this case we can see that ‘laser eye surgery’ with other qualifiers like location is much more important by search volume than ‘laser eye treatment’.
Use of N-grams within paid search
N-grams are most-widely used in Google Ads analysis as explained in this post
This N-grams analysis example from David Fothergill shows how you can review volume against other KPIs such as cost, conversion rate and ROI.
This shows the value of keywords like ‘free’ against ‘free delivery’, the former may attract visits that don’t convert while the latter has higher conversion. It can also be used to assess negative keywords to use since we can exclude keywords that don’t convert.
Resources available include this Google Ads script, another from Brainlabs and this spreadsheet approach.
Uses of N-grams within organic search
As well as the keyphrase-based analysis sheet, the Smart Insights keyword gap analysis download enables you to quickly assess the number of times a single keyword (1-gram) occurs across all keywords searched for. This is useful for long-tail analysis, for example, for a retail site we can see the number of searches by consumers for search term qualifiers like ‘prices’, ‘deals’ or ‘reviews’ and how effective we are in attracting them.
