Deadtrees.earth is an open, global data platform for mapping, analyzing, and sharing information on dead trees using remote sensing and citizen science. It integrates satellite and drone data to track the spatiotemporal distribution of tree mortality. The platform provides standardized, FAIR-compliant datasets for ecological research, biodiversity monitoring, and climate change studies. Users can contribute drone datasets, provide annotations, upload data, and access curated reference datasets for model training and benchmarking. Deadtrees.earth fosters collaborative, reproducible research by linking multi-source data and tools for large-scale forest monitoring.