Unhealthy diets (rich in calories, sugar, fat, and sodium) are a major cause of obesity. Why individuals struggle to make healthy food choices remains unclear. This study examined how body mass index, biological sex, and eating context influence food attribute perception, the food choice process, and the percentage of healthy food choices. In an online study, males and females with and without obesity (n = 910) rated food images for healthiness and tastiness and made food choices after prompts directing them to choose foods they considered healthy (healthy prompt) or to choose as they would in their daily lives (typical prompt), which aimed to model healthy and typical eating contexts. When foods were classified as healthy or unhealthy using nutritional labeling information, all participants rated healthy foods with larger healthiness ratings, but females rated healthy foods as healthier and tastier than males. Still, participants with obesity had fewer healthy choices (i.e., choosing the food with the largest healthiness rating) regardless of sex and prompt. Further, tastiness differences were more relevant than healthiness differences during healthy food choices among participants with obesity, and more so after the typical prompt. On the contrary, healthiness differences were more relevant among participants with healthy weight regardless of prompt type. Our findings highlight the importance of eating contexts in how individuals use their perception of food attributes during healthy food choices and suggest that increasing the presence of healthy prompts and perceived tastiness of healthy foods may promote healthy food choices among individuals with obesity.