Dogs' behavioural synchronization with humans is a new field of research in canine cognitive science. It has important societal implications, as dogs' propensity to mimic their owners' movements and reactions can be used as a tool to manage pets in public areas and ensure that they react appropriately when meeting third parties (humans or other dogs). To ascertain whether nonexperts can accurately assess dogs' behavioural synchronization with humans, we conducted a citizen science project via a website. A total of 731 nonexpert volunteers rated videos of dogs' behavioural synchronization with their owners while the two moved freely indoors. Interestingly, although synchrony was rated lower by the nonexperts than by the experts in canine ethology, the former understood behavioural synchronization and processed its changes similarly to the latter. Finally, all nonexperts evaluated behavioural synchronization similarly, indicating a robust perception of this synchronization across respondents.