Most SEOs and internet marketers will tell you that they rely heavily on the Google AdWords External Keyword Tool for keyword research. It’s commonly used for choosing domain names, page titles, in-content keywords, domain selling and so on.
However, what most people don’t realize is that the AdWords Keyword Tool is wildly inaccurate for most of these applications!
Let’s think about it for a minute. This is a tool for AdWords advertisers. It shows an advertiser how many times his ad may appear, i.e. how many impressions an ad will get, when it is associated with a particular keyword.
Now, what do we know about how AdWords ads are displayed? Sure, the ads show up on search result pages. But where else? How about all those hundreds of thousands, maybe millions, of AdSense publishers? Yup, anywhere an ad may be displayed counts in the AdWords Keyword Tool. So if someone has a website with a page about Green Widgets and has AdSense on that page, that counts as a possible impression for “Green Widgets.” Does that mean that term is searched? No, it doesn’t. It just means that there’s a page that Google has identified to be relevant to the term you’re looking at, and therefore that’s a possible impression for you.
Have you ever noticed that even when you rank on the first page for a term that you thought gets tens or hundreds of thousands of searches (because GAEKT told you so) you still end up with maybe only 10% or less of that traffic? This is why. The search volumes you’re looking for are not actual search volumes. They include the content network, image search and parner sites (i.e. AOL, YouTube, etc.)
David Naylor has a good post about this, along with a case study.
So now that you know the Google Keyword Tool is so inaccurate, and you know why, you probably want to know if there’s a more accurate tool for evaluating search volumes. And indeed there is.
The Google Search-Based Keyword Tool is what you want. It tells you the actual search volume for search terms. Of course, this tool has its drawbacks too. I have seen it show inconsistent results. I have also seen it show search volumes that are lower that the search activity I actually get on my sites that rank for those terms. So it’s not a perfect predictor of your search volume. But it gets much, much closer than the AdWords Keyword Tool.