How do people conduct gender classification in ambiguous contexts? A gender framing perspective suggests the pervasiveness and consequences of using gender in novel contexts, but there is a paucity of knowledge about how people assign a gender to ambiguous targets in interpersonal relations. This study fills in this knowledge gap by investigating how U.S. individuals classify the gender of two types of gender-ambiguous names—Chinese names written in English letters and gender-neutral American names. It also examines how respondents’ gender ideologies and racial stereotypes are associated with their perceptions of gender-ambiguous names. An online survey experiment with 795 U.S. individuals finds that respondents predominantly assign a binary gender (versus neutral or unsure) to both Chinese names (40.8 percent men and 37.4 percent women) and gender-neutral American names (41.1 percent men and 19.4 percent women). Multivariate analyses reveal that respondents with traditional gender ideologies associate a gender-binary perception with gender-neutral American names rather than Chinese names. Meanwhile, respondents who endorse the racialized stereotypes that Chinese people are socially cold and/or generally competent are more likely to perceive Chinese names as men’s names. These findings demonstrate that a gender-binary frame persists in ambiguous contexts, and that the classification outcome is conditional on contextual signals and preexisting cultural beliefs. They also deepen understanding of gender neutrality during social interactions and a gendered nature of racialized stereotypes.