Soil moisture, the water stored in the ground, is a key part of Earth’s water cycle. It affects extreme events such as heatwaves or droughts, and affects agriculture, water supply, and our ability to prepare for climate-related extreme events. However, measuring soil moisture accurately across the globe is difficult because different datasets use different methods, and many are only indirectly validated using precipitation or evaporation. Most of these validations are also focused on the Northern Hemisphere, leaving big gaps in the remainder of the world.The ROOTS (Re-gridded Observations Of Terrestrial Soil-moisture) project helps address this problem. It brings together more than 13 different soil moisture datasets, collected from satellites, models, and reanalysis, and combines them into a common format, with the same resolution and time scale. We directly compare these products against on-the-ground soil moisture readings from around the world using the International Soil Moisture Network (ISMN).This allows us to understand where the different datasets agree or disagree, how reliable they are in different regions, and how soil moisture has changed over time. ROOTS gives scientists, hydrologists and policymakers a stronger foundation for tracking droughts and understanding climate patterns. It is openly available and designed to support the global community.