Home Search Engine Marketing Using the Keyword Effectiveness Index (KEI) for Keyword Research

Using the Keyword Effectiveness Index (KEI) for Keyword Research

by amol238

keyword effectiveness index - KEI

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.

Image Credit: Ajkohn2001

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evan schulte July 28, 2010 - 1:42 pm

Great information. I have never really understood the reasoning behind whether or not to use a certain keyword. I have always tagged what i thought was useful. I never thought about it that way.

Gary David | Build Your List Fast July 29, 2010 - 3:34 am

Right. I also don’t mind keywords before, but I suddenly realized the importance of it lately as it can really help you rank especially if you’re into blogging or article marketing.

TriNi July 28, 2010 - 2:22 pm

Definitely sounds interesting. I wish I understood more about how it works. I’m good at Math but that just seems way over my head. I do tend to keep a good keyword to content ratio though, and it’s been working for me so far when it comes to search engines. Hopefully in the future I can learn more about how keywords affect rankings.

Gary David | Build Your List Fast July 29, 2010 - 3:35 am

That’s also way over my head, the formula seems to be a bit confusing. But he really provided a very useful information about keywords and can definitely help me with my keyword research in the future.

Roko Nastic July 29, 2010 - 6:54 am

KEI doesn’t have to be confusing at all since a lot of keyword research tools calculate it automatically. You just need to interpret it properly. Some of the tools that will calculate KEI for you are KeywordDiscovery, Web CEO, WordTracker… But don’t forget that KEI is useful only when used with other factors, it is something that can help your keyword research, not something to completely rely on.

Janet July 28, 2010 - 11:17 pm

Thanks for sharing this great post on KEI. It’s very enlightening. I absolutely love to read informative stuff. Looking forward to find out more and acquire further knowledge from here! Cheers!

daisyfreya July 29, 2010 - 2:03 am

Thanks for providing an informative post.It helps a lot to know the effectiveness of keywords.

Uzi July 29, 2010 - 11:42 am

Key ZK, This post is really awesome. I never knew the pros and cons of KEI. Thanks for explaining it in details.

David Leonhardt July 29, 2010 - 1:22 pm

KEI is a nifty little gimmick, which I believe was invented by WordTracker a number of years ago. It is so full of holes that you could plug it with Swiss cheese. And the main reason is because it is a ratio of two variables. One variable, if done properly, is a valuable variable. The other variable is 100% useless (this blog post actually illustrates this point well, but doesn’t address it directly).

The useful variable is how many searches there are for a particular keyword. Assuming the keyword is one that brings in the right type of searchers, this is a very useful variable. It is important to know the size of the market.

The second variable is totally useless – how many competitors there are. First, I should point out that there is in fact no available statistic on how many competitors there are. Google might consider 467,000,000 web pages relevant for the term “weather” (or even 2,280,000,000, as I see when I just now searched), but most of those websites are not actually competing for “weather”. Let’s assume that 50 of the sites actually are competing for the term “weather”. Or maybe just 20. Or it might be 100. Either way, the massive amount of false data included in the KEI equation makes the actual ratio meaningless.

But even if we could define exactly how many websites are actually competing for “weather”, KEI still measures the wrong metric. If your target is to get into the top 10 websites for “weather”, then the only variable that counts is how hard the current occupant of that position (#10) is competing, how hard it would be to displace. All the websites ranking below #10 is just static. In order to unseat #10, you will end up passing them all anyway. This is a race, not a battle. You don’t have to defeat them one-by-one, just pass them along the way as you target the #10 position. Same principle if you are targeting the #1 position.

The whole concept of KEI is a big red herring, providing false information. I measures an irrelevant metric, and it measures it inaccurately. Nice gimmick, useless tool.

Roko Nastic July 30, 2010 - 1:55 am

You made some good points, but that doesn’t mean that KEI is useless. I also don0t agree with the claim that it is easy to come position #10. It is easy only for keywords with low competition. For highly competitive keywords like SEO, SEO consulting, freelance writing services, website design services and similar it is very hard to enter first 100 results.

Property Marbella July 30, 2010 - 11:42 pm

KEI is a intresting formula in combination with other keywords tools. Sometime can you with KEI find a better word with little less visitors, but with much less competing web sites.

SEO Services Company August 2, 2010 - 5:34 am

is KEI gives good results, that’s nice, i never used that, but i will try to use,
thank for giving information’s.

Plumber Sydney August 3, 2010 - 4:33 pm

I’ve known about KEI for a while but your explanation helped clear a few things up. Cheers.

Start Getting Website Traffic August 4, 2010 - 4:11 pm

I don’t think KEI is something to get to hung up about, if you want to use it then let it form part of the picture.
You can get the info from Keyword Discovery as it shows the search volume and KEI.

smart metering August 5, 2010 - 1:05 am

I have come to know first time with such a great tool for keyword research and it seems very effictive. Hope it will work as effecitve as it seems.

Software Development Company August 23, 2010 - 5:31 am

Good explanation about keyword effectiveness index and how it work. I will try keyword research this method. Thanks..

Locksmith Melbourne October 2, 2010 - 11:34 pm

I’m quite new to SEO and still learning different methods of using KEI.. This article did help me implement strategies to use my KEI better.. Thanks again

Paul Fitzpatrick October 27, 2011 - 4:41 am

Thanks for clarifying KEI.

I never really understood the math behind the theory but you explained really well.

Just one question though, is this figure based on just Google/Bing/Yahoo results or does this include figures from the smaller search engines??

Thanks again.

Philadelphia SEO November 21, 2011 - 9:15 pm

Well, I’m one who uses KEI, but not as an overall deciding factor. A smart SEO professional will weigh this along with other factors, like talking to your client, market research, demographic, geographic targeting, experience, sometimes even luck. Nothing we do is a perfect science, which is why many of us are in this field. Great explanation of KEI and hopefully it helps some others using it or not using it understand this part of keyword research. Thanks.


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