As you can see, LongTailPro is pulling data from Google Adwords. WHAT?! So LTP uses a mix of their own massive data (launched in 2011) and data pulled via API from Majestic.com, Moz.com, and Google Adwords (http://adwords.google.com). Once you input your seed keywords, LongTailPro outputs suggested keywords related to your seed keywords, search volume, Adwords suggested bid, Adwords competition, total words, rank value, average keyword competition, language searched, and location searched.
The experts love SEMrush, but will you? Take the tool for a test drive and decide for yourself. For a limited time I'm giving all my readers an exclusive one month free access to SEMrush PRO. You'll get unrestricted access to all the tool's features. If you decide SEMrush is not for you, cancel anytime during the one month trial and you won't be charged a penny.
In a nutshell, Long Tail Pro helps you quickly find keywords in bulk based on a seed keyword that you input. In addition to returning hundreds of related keywords, the tool also shows search volume (monthly search volume), advertiser bid, number of words, rank value, and my favorite Keyword Competitiveness (helps you judge the competition and keyword difficulty).