The document compares several keyword research tools (Spyfu, Searchmetrics, SEMrush, Keywordtool.io, Keyword Eye, Wordstream, and Wordtracker) based on various criteria. The tools were compared on their ability to match keyword volume data to Google Keyword Planner. SEMrush and Keyword Eye showed the best matches. The tools were also evaluated based on the number of new keywords found, ease of data collection, and whether the new keywords found seemed useful based on their monthly search volumes. Based on these comparisons, SEMrush emerged as the strongest overall performer.