Recent studies highlighted that autistic individuals show increased perceptual capacity -- the ability to process more information at any one time. This study examined whether there is a link between this increased perceptual capacity and the sensory hypersensitivity that many autistic people experience on a daily basis. In total, 38 autistic and 66 non-autistic adults filled in sensory questionnaires and performed an auditory load task, which assessed perceptual capacity. Results showed that higher levels of auditory perceptual capacity were correlated with higher levels of sensory sensitivities. We identified two clusters in the sample: one group of individuals with hyposensitivity and a decreased perceptual capacity (n = 42) and a cluster with an increased perceptual capacity and hypersensitivity (n = 47). Understanding this relationship may offer the opportunity to develop more effective techniques to ameliorate the often debilitating consequences of sensory hypersensitivity and over-arousal. Interestingly, this association between perceptual capacity and sensory sensitivities was seen for both groups; no significant association was found between perceptual capacity and level of autistic traits. As such, the findings may extend to other conditions with sensory atypicalities, such as attention-deficit hyperactivity disorder or Williams syndrome. The practical implications of the results for many aspects of daily life, education and employment are discussed.