The Monthly Search Volume metric gives you an estimate of how many people search this exact seed keyword phrase in Google search each month. While the estimates aren't perfect for all specific keywords, this free keyword tool uses a technology (API) that connects to a Google search insights product. The Difficulty rating functions on a scale from Low to Medium, High and Very High, which denotes just how challenging it'll be for your blog to rank on the first page of organic Google search results for the particular keyword phrase.