fedelemflowlist is a Python package that generates and provides a standardized elementary flow list for use in life cycle assessment (LCA) data as well as mappings to convert data from other sources. This list supports the Federal LCA Commons, where preferred flows from the active version of the flow list produced by this package can be found in formats for use in LCA software. Standard formats for a Flow List and a Flow Mapping are defined and provided by fedelemflowlist. They are implemented as pandas dataframes. Standard formats are also described for the input files used in building the flow list, and implemented as .csv files in the input directory. The version of the package (see Releases) corresponds to the version of the flow list that it provides. The complete or 'master' list contains all valid flows, where the 'preferred' flows are the recommended flows for use in LCA data. fedelemflowlist can export complete or subsets of the flow list and mapping files as a .zip archive of JSON-LD files conforming to the openLCA schema. The background and methodology behind creation of the flow list, as well as a summary of the flow list itself can be found in the USEPA Report 'The Federal LCA Commons Elementary Flow List: Background, Approach, Description and Recommendations for Use'. Definitions for terms used in the flow list can be found in on EPA's Terminology Services in the Federal LCA Commons Elementary Flow List for Life Cycle Assessment vocabulary.