The authors present a first, integrated map of Brazilian land tenure encompassing all official data sources pertaining to both public and private lands.

Of the total (8.5 million km2) 36.1% of all lands are public (with 6.4% officially undesignated), 44.2% are private, and 16.6% are unregistered or with unknown tenure. Strikingly, overlaps among land tenure categories sum to 50% of the registered territory of Brazil. A clearer understanding of uncertainties in land tenure, and the spatial distribution of those uncertainties can help guide research and public policies focused on minimizing land conflicts and strengthening governance and territorial planning to improve economic, environmental and social outcomes from land use in Brazil.