How do you figure out what keywords your competitors are ranking for, you ask? Aside from manually searching for keywords in an incognito browser and seeing what positions your competitors are in, SEMrush allows you to run a number of free reports that show you the top keywords for the domain you enter. This is a quick way to get a sense of the types of terms your competitors are ranking for.
Use the Google Adwords Keyword Planner to find new and related keywords, but ignore the search volume data! The search volume data in the planner is really only useful for keywords that you’re actually spending money to advertise on. Otherwise, these volumes are not reliable. While not really helpful to decide which keyword is most used by your potential audience, Google Adwords Keyword Planner makes a useful tool in coming up with ideas for potential keywords!

Understanding the balance of terms that might be a little more difficult due to competition, versus those terms that are a little more realistic, will help you maintain a similar balance that the mix of long-tail and head terms allows. Remember, the goal is to end up with a list of keywords that provide some quick wins but also helps you make progress toward bigger, more challenging SEO goals.
But it’s still very useful for getting search volume data (provided your account still shows this), which is helpful when choosing which of the many keywords you’ve found to focus on (although you should take these estimates with a pinch of salt, they are still useful in indicating the relative search volumes of different keywords, even if the absolute estimates are a little off).

The limit on manual keywords could be higher.  I personally wish we could input 10,000 keywords at a time, instead of 200.  However, I understand the costs that Long Tail Pro has to maintain each time a new manual keyword is input.  Not a deal breaker, I just wish the limit was higher. (To be fair, I don't think most keyword tools have a bulk manual option at all).
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