It is currently unknown how many psychologists are contributing to the current replication crisis by using questionable research practices. Previous estimates vary considerably, from over 60% to near 10%. In the current work, the authors produce three estimates of the number of American psychologists who have used questionable research practices in the past 12 months, utilizing direct, indirect, and social network measures of estimation. This social network method, called the generalized network scale-up method, acts to reduce selection bias by accessing the population of interest via the social networks of participants. From 613 participants, we estimate up to 24.40% of American psychologists have recently used at least one questionable research practice. These estimates represent a first step in generating actionable interventions to resolve the current replication crisis and increase public trust in published research.