1) SEMrush - I believe that among all the 3rd party software, SEMrush has the largest keyword database. Their search volume data is pretty accurate and aligns with the Google keyword planner. Also, based on the type of content that needs to be produced (i.e. informational, transactional, etc.), one can utilize different filtering options available in it.
Search Analytics can be found under the 'Search Traffic' section and provides details of the keywords that drove clicks to your website, based on data for up to the last 90 days. The difference with Google's version is that you can filter the data to put extra context around the keywords, such as filtering by country to see keyword popularity based on country, which can be useful when carrying out keyword research for websites that service more than one country.
I learned a lot from you and now make a couple hundreds per month in extra cash thanks to your advice. You provided us with great content and a great tool. I’m very happy for you. I have to say though that I’m sad you sold… customer service is so so so far and I know it’s cool for owners to sell subscriptions instead of selling it for a one time fee and I know it’s a new trend online but it’s really a trend I don’t like as a customer… Anyways. I’m very happy for you. Many thanks and congrats !!!
Keywords are supplied with accurate, clickstream-based metrics, some of which are exclusive to Ahrefs. For example, Clicks and Clicks Per Search can give you a better idea of how much traffic your content can get. That’s a burning issue today – many queries never translate into clicks because Google reveals answers for them at the top of SERP (i.e., Knowledge Card).

1) Ahrefs to quickly see “the big picture” when it comes to any keyword I'm researching. I can instantly see the top holders in the SERPs. I then immediately take the top holders list and go check out their sites. I need to make sure I can beat them content-wise, otherwise I will search for another keyword to try and rank for, or perhaps go down the long-tail route. The Ahrefs tool and data quality get better and better every year. It's one of my favorite tools.
I was going to post screenshots here showing my numbers for the past year – but the dashboards in the old affiliate platforms (Clickbank and JVZoo) don’t provide the best visuals – so I’ll just show you my total affiliate income for the past year. In one year (March 13, 2015 to March 13, 2016) I earned $3867.60 in commissions for promoting Long Tail Pro. Not bad for having just a mildly popular ‘passive income blog’ and only a small email list!

The link back to googles API is crap – it keeps coming up with password authentication which renders it virtually useless when trying to find your own rank. Sells you the software initially. But then tries to sell you a load of stuff afterwards which effectively tells you the first version you have already paid for is useless without the extra “bonuses”. Not a nice way of doing business
Keyword Overview looks at the entered term on its own and addresses expected searches per month, the difficulty of competing against Page 1 results for the same term, a rough estimate of organic click-through opportunities (versus paid ads and non-organic positions on the search engine results page), and the perceived priority that the user should assign to optimization for this term, where the higher the score, the higher the demand and a lowered level of competition.
And so on and so on. The point of this step isn't to come up with your final list of keyword phrases -- you just want to end up with a brain dump of phrases you think potential customers might use to search for content related to that particular topic bucket. We'll narrow the lists down later in the process so you don't have something too unwieldy.
There, now. We’ve given you an overview of twenty-five cool keyword tools. Of course each of these has its own strengths and caveats, and at least for now, none can match the effectiveness of Google’s Keyword Tool, particularly in language, location, or device-specific results. Google gathers and analyzes vast amounts of data and as you know, the rich only get richer.
Analyzing the current top 10 search results in Google is the most important part of keyword research. This is where you determine whether or not you can produce a webpage that can beat any or all of those results. The process is known as first page analysis – and it is by far the hardest process to understand and really figure out (especially when you first start out). Don’t worry though – Long Tail Pro has detailed and in-depth instructional videos available that show you exactly how to do this.
The WordStream suite of Keyword Tools is an integrated and actionable set of keyword tools designed to help search marketers with keyword search, keyword suggestion, keyword grouping, PPC keyword research, keyword analysis, long-tail keyword research, and negative keyword discovery, going beyond the capabilities that a typical free keyword tool can offer.
This comes with a monthly fee though, so why have that recurring revenue drain when you can just get MS or LTP for that matter on a one off fee. They are both virtually the same in my opinion. This is the only thing that is stopping me from buying the software. If the calculation of keyword difficulty was included in the one off fee, i wouldn’t mind paying the full $97.
I want to share how and why I sold the company in order to both educate and inspire potential software entrepreneurs.  I certainly don't know everything and obviously companies sell for much more than I sold Long Tail Pro for (I won't be featured in Tech Crunch anytime soon); however, I'm willing to share what I have learned and hopefully that can be beneficial to a few of you.