Summary1. The study of fossil and modern pollen assemblages provides essential information about vegetation dynamics in space and time. A major methodological component of these studies is the identification of pollen grains to plant family, genus and species. This identification is achieved through the use of pollen keys and reference collections of physical specimens, which are regional in scope, disparate and incomplete, slowing the identification process. Reference material is also held in museums and research institutions, where access can be limited. Identification is particularly challenging for those new to the field, such as graduate students. 2. To aid the identification of pollen grains, and provide virtual access to reference material, we present a new online tool: the Global Pollen Project (https://globalpollenproject.org). The project aims to enable people to share and identify pollen grains and through this, will create an open, free and accessible reference library for pollen identification. 3. The online tool has been developed as an open, peer-reviewed database of global pollen, where content and expertise is crowdsourced from across the world. The tool enables: (i) the submission and identification of unknown pollen grains; (ii) the submission and digitisation of existing 'physical' reference collections and (iii) the availability of a free public database of pollen images and their metadata, for use in scientific research and education. The tool connects to external services, including the Global Biodiversity Information Facility and Neotoma Palaeoecology Database, to provide botanical descriptions and occurrence data for each taxon, alongside pollen images and metadata. 4. The database currently holds information for over 1500 species, from Europe, the Americas and Asia. As the collection grows, we envision easier pollen identification, and greater use of the database for novel research on pollen morphology and other characteristics, especially when linked to other palaeoecological databases, such as Neotoma.