List of fern families

Below are lists of extant fern families and subfamilies using the classification scheme proposed by the Pteridophyte Phylogeny Group in 2016 (PPG I).^[1] The scheme is based on molecular phylogenetic studies, and also draws on earlier classifications,^[1] particularly those by Smith et al. (2006),^[2] Chase and Reveal (2009),^[3] and Christenhusz et al. (2011).^[4] It rejects the very broad circumscription of some families used by Christenhusz and Chase (2014), whose Aspleniaceae corresponds to the entire suborder Aspleniineae of PPG I.^[1][5]