Gender and age bias is well-documented in academia with many studies demonstrating bias in students' evaluations of instructors. Failure of an instructor to meet gender or age-based expectations can translate to lower scores or negative comments on evaluations. While there is some evidence of bias in students' evaluations of online instructors, current studies have not fully examined the relationship between bias and instructor vocal characteristics. First-year dental students at two institutions were randomly assigned one of four videos on spinal cord anatomy to view. Videos contained identical content but were narrated by individuals of different gender and age (younger man, younger woman, older man, older woman). Students completed a content-based prequiz, watched the video, completed a postquiz, and answered a questionnaire evaluating the video and instructor. Students at Institution A rated the younger man and younger woman highest for nearly every evaluation category. At Institution B students rated the older man and younger woman highest. Results reveal that the older woman's voice received the lowest rankings for nearly every question in both samples. This report confirms the presence of gender and age bias in student evaluations of instructors in an online environment and demonstrates that bias may surface in response to vocal characteristics. Bias may impact older women more significantly than other groups. Differences in results from Institution A and Institution B suggest that factors affecting student perceptions of instructors, and the roles that gender and age bias may play in student evaluations, are complex and may be contextual.