Online hate speech is a concern for social media platforms, regulators, scholars, researchers, and the public. Considering the prevalence and controversy of hate speech, little research has been reported on hate speech perception and its psychosocial predictors. Our study examines the differences in the perception of hate speech toward migrants in publicly available online comments between a public group (NPublic= 649) and an expert group (NExperts = 27). We also test how well the proposed hate speech indicators (characteristics of a comment) correlate with perceived hate speech in both groups. Furthermore, we explore predictors of hate speech perception by correlating it with demographic and psychological variables (i.e., human values, prejudice, aggression, impulsiveness, social media behavior, attitudes toward migrants and migration, and trust in institutions). The results indicate that the public and experts are not equally sensitive to hate speech. The expert group perceived the comments as more hateful and emotionally hurtful compared to the general population. By contrast, the public agreed more with the anti-migrant hateful comments. The proposed hate speech indicators and especially the total score correlate very strongly with both the public’s and experts’ perceptions of hate speech. Psychological predictors such as the human values of universalism, tradition, security, and subjective social distance/closeness are significant predictors of online hate speech evaluation. Our findings highlight the need for public and scholarly discussions, more robust educational policies, and intervention programs with specific measures to counter hate speech online.