Nucleic Acid parameters are obtained using X3DNA-DSSR version 2.4 for each defined biological assembly of a structure entry that contains nucleic acids. The Protein Data Bank now offers Assembly CIF files for every biological assembly; these are used as the input files. Symmetry-related chains, if present, are identified with "-#" extensions of the original chain id, e.g. A-2 is a symmetry related copy of chain A. The Summary tab lists author chain ids and number of symmetry copies present for the defined biological assembly, as well as total counts of nts, basepairs, helices, and single strand segments.

Definitions for each listed parameter are provided on NAKB nucleotide and basepair standards pages.