Extrapolating Google volumes from the Bing volumes

[Harbor_Compliance]

What would you give someone as a general rule for extrapolating Google search volumes from the Bing volumes?  I'm looking at the Moz keyword analysis tools and only Bing search volumes are listed so I'm wondering how I could those figures to estimate Google search volumes.

[Cyrus-Shepard]

Practically speaking, in my experience the difference ranges from a 1:1 relationship to a 1:8 relationship, which is a huge spread.

A lot of SEOs I know, including our tools developers here at Moz, have shown an interest in Grep Words. Might be worth checking out if you were interested.

[DougRoberts]

In order to do this with any degree of accuracy you'd need to have a deep understanding of who is searching for the particular query. Once you've got that demographic (nationality, market segment etc) nailed, you'd then need to establish the number of these type of users who use bing vs google and then multiply the volume to get something close to the Google volume.

BUT It's not something you really need to do and I certainly wouldn't suggest trying. What you're looking at when you're comparing keywords is the relative volumes between the different keywords you're researching as you look for that holy grail of high volume / low competition.

To get the Google keyword volumes you're going to have to use the Keyword Planner in Adwords I'm afraid - and even then the keyword volumes are bucketed.

I tend to have already established a list of potential target keywords/topics before I start my research using the keyword difficulty tool to determine whether they are realistic to chase and whether they should be short term or long term goals.