Few tools are available to comprehensively describe the unique social-emotional skill profiles of youth with autism spectrum disorder (ASD). The present study describes the usability, reliability, and validity of SELweb, a normed, web-based assessment designed to measure four core social-emotional domains, when used to measure these skills in a sample of 57 well-characterized youth with ASD (ages 6-10 years with IQ ≥ 80). SELweb measures facial emotion recognition, theory of mind, social problem solving, and self-control. SELweb was well tolerated and yielded scores with reliabilities comparable to those found in normative samples. SELweb scores showed good evidence of convergent and discriminant validity for three of the four skills it was designed to assess. Mean deficits were found for theory of mind, social problem solving, and self-control, whereas no mean deficits were found for emotion recognition. Individual profiles varied considerably, suggesting the sensitivity of SELweb to the within-and between-person individual differences among youth with ASD. Findings support the usefulness and accessibility of SELweb as a tool for measuring complex socialemotional skill profiles in youth with ASD.Lay Summary: No single, simple, high-quality test exists that measures multiple social thinking skills directly in children with autism spectrum disorder (ASD). The present study suggests that SELweb, a web-based assessment system, is an effective and valid way to measure how children with ASD think about and understand social and emotional information, and is able to capture strengths and weaknesses experienced by children with ASD.