In scholarly research, racial categories are typically taken for granted. However, race categories vary over time and geography and reflect the social beliefs of the people who use them. Informed by quantitative critical race theory analysis, we interrogate how race categories align (or not) with 24,000 U.S. higher education students' responses to ethnoracial identification questions. Students provide a wide range of ethnoracial categorizations when prompted with an open-ended instrument: ethnic/national identities, panethnic identities, resistance to categorization, unknown origins, and racially mixed identities. Quantitative methodologists recommend that survey researchers not use a write-in or open-ended format for racial identification because it introduces error and ambiguity. However, students' responses show that the race categories provided were not exhaustive or mutually exclusive. This work has policy significance because in early 2024, the U.S. Office of Management and Budget recommended that federal agencies provide respondents with a write-in box and detailed categories when collecting race data.