Diverse students in K-12 schools face many challenges to succeed, including the cultural incongruity between their home cultures and school. A widening achievement gap over the pandemic has prompted research from the culturally responsive teaching (CRT) perspective. This quantitative study aims to understand K-12 teachers' self-efficacy in CRT and to identify specific aspects of teacher preparation that may contribute to teacher confidence in CRT. Data was collected from teachers (N = 564) nationwide using the Culturally Responsive Teaching Self-Efficacy (CRTSE) scale during the 2020-2021 school year. Findings suggest that teachers are less confident in teaching strategies addressing cultural differences. Specific types of teacher preparation were found to be significant factors in raising teachers' CRT confidence.