A system and method that facilitates and effectuates distinguishing a human from a non-human user. A human interactive proof (HIP) employs a partial credit algorithm in order to allow a user to make one or more mistakes during consecutive HIP challenges and still be identified as a human. The algorithm assigns a user partial credit based upon getting part of the challenge incorrect. The partial credit is tracked and if during one or more consecutive subsequent challenges the same user gets a portion of the challenge incorrect again, they can still be identified as human.