FDRdb is a powerful tool that helps researchers to explore functional mechanisms of deregulated RNAs in fibrotic diseases. In this interface, users can input mRNA/miRNA/lncRNA/circRNA/siRNA symbol or disease to obtain the fibrotic disease-associated RNA information. FDRdb also provides pull-down menus to enable users to select all or particular species and tissues. The search case is also provided below the search module for reference.