Ubersuggest is a fantastic option for agencies that want to do SEO work but have smaller SEO budgets, or no budget at all. The tool is still completely free and will provide enough information to understand basic keyword data. The big difference between Google Keyword Planner and Ubersuggest is that long tail keywords are shown within the Ubersuggest dashboard. Long tail keywords essentially search terms that are more than 2-3 words. For a free keyword research tool that displays data for long search phrases and terms, this is your best option.