The Yale–Brown Obsessive Compulsive Scale (Y-BOCS) is a test to rate the severity of obsessive–compulsive disorder (OCD) symptoms.

The scale, which was designed by Wayne K. Goodman and his colleagues, is used extensively in research and clinical practice to both determine severity of OCD and to monitor improvement during treatment. This scale, which measures obsessions separately from compulsions, specifically measures the severity of symptoms of obsessive–compulsive disorder without being biased towards or against the type of content the obsessions or compulsions might present. Following the original publication, the total score is usually computed from the subscales for obsessions (items 1–5) and compulsions (items 6–10), but other algorithms exist.