If the closure of the popular Google Reader service has taught us anything, it's that no program is safe from the search giant's chopping block. The next one expected to make an untimely exit is the popular Google Adwords External Keyword Research Tool.

The free Adwords tool has commonly been used by webmasters to uncover such statistics as keyword search volume, estimated traffic volume and average cost per click. It has proven particularly valuable when it comes to determining which specific keywords a webmaster should target with future search engine optimization (SEO) and pay-per-click (PPC) campaigns.

Though the exact date for the shutdown hasn't been confirmed, it's expected to occur soon. Google says the Adwords tool essentially will be rolled into a new program called the Keyword Planner. In the future, webmasters hoping to access Google's keyword data bank will be required to create advertiser accounts. As of now, it doesn't appear that users will have to spend money on paid advertisements to access the Keyword Planner, though there's no way for sure to know whether Google is headed in that direction.

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The biggest difference between the new Keyword Planner and Google's former tools is its structure. While the External Keyword Research Tool contained a number of disjointed workflows, the Keyword Planner has one clear purpose: to help advertisers create new PPC ad groups and ad campaigns as quickly as possible.

To support this objective, the Keyword Planner uses an interface that allows users to start by searching for keyword ideas, uploading keywords to get estimates or multiplying keyword lists to get estimates. Regardless of the option you choose, you'll be able to brainstorm keyword ideas using a number of different methods and filter keywords according to a robust set of criteria.

Some users might be disappointed by information that seems to have gone missing from the Keyword Planner, specifically ad share statistics and local search trends. It's also unclear what the impact will be to the dozens of keyword research tools that rely on data from the External Keyword Research Tool to power their searches.

If you use the External Keyword Research Tool to drive the development of your website in any way, take the time now to familiarize yourself with the new Keyword Planner to avoid any delays when the final transition occurs.

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