All these tools collect information from different databases, but with relative similarity, remember that most of them use Google Keyword tool (planner now) and mix it wit other results.
To make things clear, try this:
Use Wordtracker and Longtail first, then compare that result with Google Keyword planner, if you find very small traffic in Adwords, you should eliminate that keyword and go to the next one, so my advice is compare these results with adwword all the times.

All tools use google keyword tool to get data so google Keyword planner is the best one...

Keyword planner or market samurai ...never failed me yet. If you want to discover just go deeper in your KW research by using Google trends to discover more info on the keyword besides search volume. Google trends will give insight on the keyword as well as GEO information and jnterest on the keyword.

I only use only Google Keyword Tool and it is enough to find keywords which makes £1K daily. There are many tools out there, but I'd say that the Keyword Tool does everything you need.

I'm with Google Keyword Planner since it provides more accurate information than any other tools.

LongTailPro and WordTracker are better options, they show much more accurate searches where google hides.

Google keyword planner along with google suggest (or ubersuggest.org) is good enough for keyword research. For finding long tail low competition version of a seed keyword you can use keywords from ubersuggest and upload it into google keyword planner.

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If you find anyone better than Google Keyword Planner then let me know too...:rolleyes:

I have not had much success with new Google keyword planner. To be honest I don't think you need to rely on Google keyword planner results, you need to use your skills to find out the most optimum keywords for your SEO campaign, after all you know your target audience better than any of the tool. Though many of the times it does happen that we go blank while keyword research and cannot find the start point. I use freekeywords.wordtracker & Ubersuggest for keyword suggestion and then I go with the satisfying keywords.

You can also find relevant keywords in Google instant and Searches related to "Keyword" column which are really helpful.

Hope this helps!

I use Google keyword planner and ubersuggest.org. Both are very good and free.

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word tracker and keyword planner are the best tool to research keywords.

Netpeak Checker and SEMrush

I am yet to understand the new features of Google keyword planner. Used Google keyword tool a lot before.

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i use soovle.com . what i like about it that it shows multi search engines keywords on same page

Keyword research tool is the best and to be efficient you definitely need to be have the excellence in this because they can give you the present scenario which is actually helpful for the SEO. this is very effective and not very difficult too.

Mostly People using Google Keyword Planner, But word Tracker is the best.

Keywords Adward tool is best option to get ideas of your keywords and its seaches.

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