Hi, Great article! the tools you listed in this article are great. I tried only Keyword planner and at present I’m using a long tail pro for Keyword search but I didn’t try the other tools you said. Because I’m new to this and now only I’m learning one by one. At this time, I thought this guide will help me to know more about keyword search tools. It’s wonder and thank you so much for this nice guide. 

As for duplicate content, Google gets confused when you create and publish articles with similar content, and this eventually leads to indexation issues. Keyword cannibalization happens when the owner focuses his effort on ranking for a particular keyword from several different pages. When this happens, Google won’t acknowledge multiple pages; they’ll only focus on the best one thus making the other ones useless and inaccessible to search engines.
Jaaxy without a doubt provides the value needed to justify the 3 price ranges. I have switched to only Jaaxy as I have found the data provided is amazingly accurate and all the features available really make SEO and Keyword research easy. Jaaxy is fantastic for Niche research and once inside there is training available to assist with that and while you find a great niche you can also find out if the domain name is available and click to purchase easily.  Infact I have a post about using Jaaxy to find a niche market https://webincome4me.com/how-t…
What this does is give you an idea of how realistic it is for you to target keywords with high commercial value. You want to go after keywords with some volume, because they’ll have a better return in terms of traffic. But you don’t necessarily want to go after the most competitive keywords, because you’re less likely to be able to rank for them. You’re looking for a sweet spot.
What is KWFinder? Well, KWFinder is really an alternative to Google’s keyword planner, which just sucks. Anyone that uses AdWords or any of Google’s tools on a daily basis know that they are just very clunky and the UI is lacking. But of course, it is free so sometimes you can’t be too picky. But in my opinion, if a tool provides real value and speeds up my work, then it is worth every penny.
1) Google Keyword Planner: This tools is fantastic because it can help me to identify long tail keywords for my niche. It is official Google’s tool and it has the recent trends and keyword variations. For example you may think that this keyword is great “buy ipad air in liverpool” but Google may suggest “iPad air sale Liverpool”. Yes, not often it is accurate but when I’m using it alongside the other tools – I can get clear idea.
The Google Keyword Tool is SUPER helpful for building a foundation for your keyword research strategy. At the end of the day, these search numbers are coming straight from the horses mouth. You can filter down to a hyper-local level and see which keywords are getting the largest search volume. Plus, with it’s integration with PPC you can get a quick idea about commercial intent by looking at the bid and competition metrics. How much are people bidding on KWs, higher = more likely to generate a return. Usually its aligned with search intent. That said, the trending data is a little less reliable. I would still use Trends to analyze the popularity/ seasonality of KW search volume.
Remember, again since the Google AI is tracking real user behavior and using that as a quality signal - we are trying to avoid the scenario where the user visits out page and then clicks the back button which effectively takes him back to Google to search again or continue the search. If this happens, it indicates that users did not find the information they are looking for on our site.
However, this does not mean you cannot topple them. It just takes more of an effort in terms of content as your page has to build the trust. That is why you will see the "Google dance" happening for fresh content from a site that is not yet trusted or is not very authoritative. Google gives your page a chance and measures user click-throughs when it pushes you to certain spots in the SERPs and then measures user engagement levels when the traffic hit your site through those positions in the SERPs.