JournalGuide, the service that helps you find the most appropriate journal for your research (blog post) has just released an interesting functionality. As an effort to fight against predatory journals, they are providing a Verified label for all journals that meet their level of expectation for journal. The details about the criterium used to grant the Verified status are explained in details in a white paper and a JournalGuide blog post.
Of note, JournalGuide chose to remain inclusive keeping the journals that could not be verified in their database. Those not designated as Verified are not necessarily fraudulent, they simply could not be verified using the criterium chosen. If you wish to publish in an unverified journal, the best method is to ask around. If your colleagues had a good experience, chances are you will too.