3) Google: This is pretty straight forward but it’s the main reason I like it. I search for my main seed keyword in Google, and use the keywords that Google itself highlights in bold on the search results, plus the “Searches related to” section at the bottom to get keyword variations or LSI. That’s basically what Google is telling you that topic is about. No need for a thousands other tools. I use these to optimize the on page of my target pages as well.
This keyword research tool is effective, automatically providing you with keyword suggestions that other sites haven’t necessarily turned up (which it’s intended to do), along with their search volume, CPC, and Adwords competition. In order to get any actual information about the keywords, though, you need to upgrade to Keyword Tool Pro (which is a little misleading on the site copy). This plan is $88 a month, and if you’re just doing keyword research for Google, I’d recommend choosing one of the other tools for the price.

SEMrush is a very useful tool for both researching competitors when starting a site or for growing an established site. I really like to find weaker niche sites that still seem to be ranking for lots of keywords; SEMrush helps me see what they are ranking for and what I can potentially target. You can also see what keywords you’re on the cusp of ranking for with your established site - another very useful feature.
Ever since Google announced the impending demise of the AdWords Keyword Tool and their preference for its new avatar – the Keyword Planner, yet another hot discussion has sprung up in the SEO community. This time, strong adherents of the free-for-all ideology are riled at Google’s decision to make the Keyword Planner accessible only to marketers who’ve explicitly signed up to Google’s AdWords (which is one step more than having a Gmail account), taking it closer to being a paid tool in future! I don’t see this as a hindrance, because most other keyword (or other) tools require you to create an account and sign in before you can use them, even if they’re free. But if Google does it, we have reason to pounce on them, don’t we?
Successful SEO requires multiple interrelated activities on all fronts: competition, keywords, link building, on-page and technical optimization. It creates a need for diverse tools, which is expensive. SEMrush solves this problem with an award-winning all-in-one toolkit that includes 17 tools covering all SEO fields. We’ll walk you through your SEO workflow, explaining how to get the most out of our toolkit.
3. Ninja Outreach: Full disclosure this is my own tool, and it is actually an outreach tool, so you may be wondering how it plays into Keyword Research. The fact is there are quite a few data points that NinjaOutreach gets for me that I find useful in keyword research, such as the articles that are ranking for the keyword in Google, their domain authority, their page authority, the number of backlinks they have, and other social and contact data. It's pretty valuable stuff, especially if there is going to be an outreach campaign tied into the keyword research. I wrote a great article with Jake from LTP showing the combination of the two tools.
The developer of the program Spencer has even modified the program to make it better and faster. Recently, a platinum edition of the software was released. This was to help webmasters in their internet efforts. The new version simplifies the competition process, because it allows its users to store their favorite keywords and get them anytime they need them. Moreover, the newer version makes it easier for its user to track their website ranking in all the search engines.
I use Ahrefs to find ideas for keywords to add into content, and content to create around keyword opportunities. I like how Ahrefs shows keyword difficulty, search volume, traffic potential (how much organic search traffic it’s possible to get when you rank #1 for a parent topic keyword) and lets you group keywords together to create lists. It’s really useful.
As for the history of the company, as I explained, I created Long Tail Pro back in 2011.  At the time, I was creating tons of niche sites and was doing alot of keyword research and content creation.  I was trying to figure out what types of keywords would rank quickly in the search engines, specifically Google, and I was frustrated with the other keyword research tools (in particular Market Samurai) out there.