Task accuracy is a performance metric in machine learning and natural language processing that measures the proportion of evaluated inputs, questions, or problems for which a model produces an objectively correct response. Expressed as a percentage or a decimal value between zero and one, it quantifies how effectively a system meets ground-truth requirements across a specific benchmark or dataset, such as multiple-choice evaluations, classification, or open-ended question answering. This measurement directly reflects the operational competence and overall proficiency of a model on a given assignment, distinguishing the correctness of its primary outputs from secondary capabilities such as calibration, certainty estimation, or self-evaluation.