Input file should be in the standard CIF file format (https://en.wikipedia.org/wiki/Crystallographic_Information_File).
Input file should be in the standard PDB file format (http://www.wwpdb.org/documentation/file-format-content/format33/v3.3.html).
Up to 10 files in CIF, CIF.gz or PDB format can be uploaded at once. These can be different models of the same structure (as in this example) or any other set of structures.
For detailed information on other options, see Analyze your structure.
For detailed information on the resulting plots and topological fingerprints, see How to interpret knotting data.
