Using the good ol' free Google Keyword Planner is great. But there is an alternate universe of Long Tail keyword phrases that live in Google's other database--namely, their "Autocomplete database." That's the database that is accessed when you're typing queries into the Google search box (notice that list of suggested keywords that pop up as you type?)
1 – I’ve found a niche with low competition and good CPC . but the thing is the while doing competition analysis. I observed that most of the sites that are in the top 10 serps ranking are small ecommerce site selling their own product or sites like niche specific classified ad site with low and thin content. What are your suggestions ? Should I go for such keywords ?
You can also ask Long Tail Pro to get extra information like “Global Search Volume” (amount of monthly searches globally for each exact-match search term), “Domain Availability” (to see if exact-match domains are available), “Google Title Competition” and “Bing Title Competition” (this is the “allintitle” search that checks the number of sites that are using the same keyword in the title of their pages).
The “Starter” tier, with 1000 keyword lookups every 24 hours should be enough for anyone starting out in blogging – or even people who are quite established. It’s pleasing to see a product where they don’t seem to trick you into having to pay for a more expensive version. On the more negative side, I did feel that you’re nudged towards doing annual payment, with the monthly option kept slightly “hidden.”
This is one of the best articles on Keyword research tool that I have encountered. However, To add more to this, I just wanna point out a tool (LSI Graph) for an outstanding long tail & semantic keyword research. After the recent Google algorithm, Google is now, however focussing more on context & semantics than keyword alone. What do you think about it?
Google Suggest isn’t exactly a tool, but I’ve found that it can be useful for identifying potential keywords. As you type a query on, Google Suggest recommends search queries based on other users’ search activities. These searches are algorithmically determined based on a number of purely objective factors (including popularity of search terms) without human intervention. The Suggest dataset is updated frequently to offer search queries that seem to be trending upwards. This feature is largely one of the reasons that you may see repeat traffic of seemingly long tail keywords. By identifying these long tail keywords and optimizing for them, marketers can capitalize on seemingly obscure keywords with little competition.
Analyze Keyword Difficulty – Targeting difficult keywords with the highest competition is not always the best idea. The SEMrush Keyword Difficulty tool helps you determine keywords’ difficulties. By indicating a particular keyword’s percentage of difficulty, this tool helps you estimate how easy it would be to seize your competitors’ organic positions in the SERPs.
In Keyword Planner, formerly known as the Keyword Tool, you can get search volume and traffic estimates for keywords you're considering. Unfortunately, when Google transitioned from Keyword Tool to Keyword Planner, they stripped out a lot of the more interesting functionality. But you can make up for it a bit if you take the information you learn from Keyword Planner and use Google Trends to fill in some blanks.
You can try DeepMiner. It is good for scrapping, rank position, generating long tails and keyword suggestions. You can export the data to document for later analytics. You can find popular keywords that people are searching for. 7 major engines are supported, Google, Yahoo, AOL, Amazon, YouTube, Ask, Bing. It supports multi-threading so it is very very fast scrapper. BTW you must use proxy list if you plan to scrap thousands and thousands of keywords.
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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).
The simplest KW research tool is google. Type in your topic and scroll to the bottom to see what related results show up. Use those to either write an article or to supplement other articles with some of the keywords. Yes, they are primary phrases so you may not rank for them right away but building your site with these in it will help get rank for them eventually. Also look at what other articles that show up for the keyword use.

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Following a very busy (and lucrative) 2015, I’ve decided to take the majority of 2016 off and use the time to invest in various relationships and things that really matter in the long run. But in the midst of this “time off,” I’ve learned so many lessons and picked up new skills and seen new perspectives that I would never have been exposed to had I just kept on grinding away at the existing business.