9 pages, 1 figure, 7 tables. The article is part of the DiPLab ("Digital Platform Labor") research project. For more information: http://diplab.eu/Il s'agit de la version anglaise du document hal-02021525.Microwork platforms allocate fragmented tasks to crowds of providers with remunerations as low as few cents. Instrumental to the development of today's artificial intelligence, these micro-tasks push to the extreme the logic of casualization already observed in "uberized" workers. The present article uses the results of the DiPLab study to estimate the number of people who microwork in France. We distinguish three categories of microworkers, corresponding to different modes of engagement: a group of 14,903 "very active" microworkers, most...