Online classes hold the potential to expand college access to Black, Latino/a/x, Indigenous, and other students of color who must be supported to diversify the STEM workforce. Research shows that fostering belonging is key to the academic success of students from minoritized groups. However, online classes often lack interpersonal interactions and are often left out of research about the positive impacts of belonging. This paper summarizes an equity-focused STEM grant project that produced an openly-shared online professional development program, the Humanizing Online STEM Academy. Through the Academy, STEM faculty are introduced to a model of humanized online teaching that centers belonging as a way to address equity gaps. Participant survey responses present opportunities for future research about belonging in online courses.