The TNRS R package (also known as RTNRS) provides access to the Taxonomic Name Resolution Service API, which is a tool for automated standardization of plant scientific names. The TNRS corrects spelling errors and alternative spellings to a standard list of names, and converts out of date names (synonyms) to the current accepted name. More information on the TNRS is available on the BIEN website (https://bien.nceas.ucsb.edu/bien/tools/tnrs/), and the code underlying the TNRS is available on Github at https://github.com/ojalaquellueva/tnrsapi.