Sometimes we might have to know the list of users, groups and ids such as userid and groupid on macOS system. There are several ways to find this information. dsacacheutil: The command dscacheutil -q group will output all groups with their name, ID numbers, and list of members. The command dscacheutil -q user will output name,uid, gid, dir, shell, gecos details. Note: The above command will output all the groups and user details , including built-in system ones mortals were never meant to see. Check user and group association: We can run below command to check user and group associations to know whether a user belongs to a group or not. dsmemberutil checkmembership -u 501 -g 1 user is not a member of the group Or dsmemberutil checkmembership -U user -G staff The user user cannot be found There was an unknown error. User not found Alternative methods to find group and user details on macOS To list users