International Plant Names Index

The International Plant Name Index (abbreviated as IPNI) is a database of botanical names. It includes names of seed plants, ferns, and "fern allies". Coverage is the best at the rank of species and genus. It includes basic bibliographic details, along with the names. The goals of the IPNI are to eliminate the need for repeated reference to primary sources for bibliographic information about plant names.

IPNI is the product of collaboration between Royal Botanic Gardens, Kew (Index Kewensis), Harvard University Herbaria (Gray Herbarium Index), and the Australian National Herbarium (APNI). The database is a collection of names registered by the three institutions and they work towards standardizing the information. The standard of author abbreviations recommended by the International Code of Botanical Nomenclature is Brummitt and Powell's Author of Plant Names, a digital, updated version of which can be found online at IPNI.

IPNI is available at ipni.org, free of charge. It provides names that have appeared in scholarly publications, with an objective of providing an index of published names rather than prescribing accepted botanical nomenclature.