Using the Keyword Effectiveness Index (KEI) for Keyword Research

KEI stands for ‘Keyword Effectiveness Index’ and is a ratio value designed to give some idea of the importance of a particular keyword. This system of keyword evaluation is becoming increasingly popular and can be a useful tool when it comes to selecting any keywords you intend to use.

What Does KEI Do Exactly?

KEI measures and compares the demand for a keyword, against the number of web pages that include that particular keyword. These web pages will be your keyword ‘competition’. The demand is measured by “Daily World Searches” and this is calculated from the “Approximate Monthly World Searches”. In simpler terms, the “Approx Monthly World Searches” are divided by 30 to give a “Daily World Search” result.

Technically, the actual formula is:

((MS/30) ^ 2) /C

*Where MS = Monthly searches and C = Competition

Here is a breakdown of that formula:

1. Take the Approx Monthly Searches for any given keyword and divide it (/) by 30.
2. This sub-total is then squared (multiplied by itself – ‘^’).
3. This result is then divided by the total competition (number of web pages competing for that keyword).
4. The figure you end up with is the KEI ratio value.

You can perform this sum manually, or you can do like most people do and use a free program like “Web CEO”, or more in-depth software such as “SEO Elite”. Both show KEI ratio values in keyword analysis.

What Does the KEI Ratio Result Mean?

As far as the final result for a keyword is concerned, it can be judged as this:

< 0.001 = Poor keyword

0.001-0.010 = Good Keyword

0.010-0.100+ = Excellent Keyword

The higher the KEI ratio the better the keyword is deemed to be. A high KEI ratio means that the keyword is not only popular (more people are searching using that keyword), but there is also low competition (fewer websites show up as relevant results in search engine results pages.

Theoretically, this should mean that it will be easier to rank highly in the search engines for that keyword. It is advisable to use KEI as guideline only and in conjunction with other methods.

The Problem with the KEI Ratio

The KEI ration can be a good indicator of keyword popularity versus competition but there are some flaws. KEI ratios can throw up some false positives.  A keyword, or key phrase, with low competition and low monthly searches can result in a high KEI value – indicating that it is an excellent keyword.

Here is an example:

A keyword could have an Approx Monthly World Search of 200 and a competition of 1000.

MS/30 (200/30) = 6.66

^ 2 (6.66×6.66) = 44.4

/ C (/1000) = 0.04

*0.04 would indicate that this is an excellent keyword.

You could undoubtedly rank for this keyword – but would you really want to opt for a keyword that only receives 200 searches a month? If the competition was from sites with a good PageRank, or well-established authority sites, it would be extremely difficult to get on the first page of a SE.

Another example where the KEI value may be misleading is when there is massive competition, but also massive popularity.

Take the keyword ‘weather’. At the time of writing, the Approx Monthly World search for “weather” is 18,904,000 and the Competition is 467,000,000.

This results in a KEI ration of 850.253.

That would be an incredible KEI value – but the result is worthless, for two reasons:

1. You should think twice before targeting a keyword with 467,000,000 competing web sites.

2. The top ranking sites for this keyword are PR7 and above, there would be little chance of competing against them.

Is the KEI Ratio a Waste of Time?

The KEI ration can be very useful, when it is used in alongside other methods of keyword research. If you do the KEI method for keyword research (it is featured heavily in popular keyword analysis software), try not to rely solely on the KEI value. Use your common sense and look at the popularity and amount of competition and do some in-depth research of the top ranking sites.

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