These keyword research tools should make it easier to create a list of relevant search terms. You should make sure to create awesome landing pages for keywords you want to be found on. You should also think about cornerstone content articles and a great internal linking structure in order to make your SEO strategy complete. In our SEO copywriting course we dive much deeper into keywords, landing pages, and long tail keywords.
What I really like about them is extensive detail including the keyword difficulty. Ahrefs uses clickstream data to also show how many clicks you will get from the search engine. This is very useful after knowledge graph integration, as many keywords may have huge traffic but they hardly get any clicks from the search engine. Reason being, they get answers directly from the Google search result. Example of one such query is: “birthdate of any celebrity”
"With Google giving over the home page to ads and their own properties for commercial keywords, the Long Tail keyword is more important than ever. If you have a website, you know that most of your traffic comes from keywords you never would have thought of. With Keyword Researcher, you can find them in advance and make sure that you're the one that snags this traffic. I use it for all of my e-commerce site planning."

While this one isn’t necessarily a keyword research tool, it will give you valuable insight into how the keywords you’ve been optimizing for so far are actually performing for you. You might realize that you could start ranking for more keywords with more difficult competition, for example, or that only keywords on certain subjects are working for you.

The Google Keyword Tool has a variety of helpful features meant to streamline the keyword research process. By entering terms or phrases into the search box, the Keyword Tool allows you to build extensive, relevant keyword lists from one simple interface. By default, the tool displays Advertising Competition, Global Monthly Searches, Local Monthly Searches, and Local Search Trends for each keyword. Additional options allow marketers to show the estimated Average Cost per Click, Ad share, and Search Share.

How do I know this? Because I’ve done it! In late 2013 I was still struggling to earn a respectable income online. I started up a keyword research service and marketed it to just this blog audience. It turned out to be quite popular. Basically – I would find niches using Long Tail Pro then create Keyword Research Packages. Each package contained usually several hundred keywords with KC scores calculated. I was selling these packages for anywhere between $97 to $147. I even sold one single package for $597! That one had very high search volumes and very low competition.
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).