Keyword Suggestion Tool

shows the per day keyword results from both Overture and Wordtracker. Wordtracker breaks the results down in plural and singular where Overture combines them together. For example Overture reports "anime wallpage" as 2609 per day where Wordtracker shows "anime wallpaper" with 3160 per day and "anime wallpapers" with 1948 per day. The different totals don't matter, it is the plural/singular percentages that you need to help you decide which keyword to target.

Source: http://www.digitalpoint.com/tools/suggestion/

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