<strong>Background:</strong> Keratoconus (KC) causes visual disability in young adults. To improve its early detection and compliance, improving the awareness of patients and their relatives is crucial. We present the level of awareness about KC among the adult population of western Saudi Arabia and its determinants. <strong>Methods:</strong> This web-based survey was carried out from June to August 2020 in urban and semi-urban areas in western Saudi Arabia. Demographic and eye ailment profiles were collected. To generate responses on the presentation, causes, management and prevention of KC, a five-point Likert scale was used. The logit values were calculated and graded into good and poor awareness. Awareness was associated with other determinants. <strong>Results:</strong> We surveyed 420 Saudi adults. The median logit score of awareness about KC among participants was 2.86 (inter quartile range (IQR) 0.86;2.95). The median score of knowledge about the causes and presentation of KC was 2.86 (IQR 1.1;2.86) and for management, it was 0.00 (IQR 0.00;0.18). The level of awareness was good in 286 participants (68.1%) and poor in 134 (31.9%). Residents of major cities (P < 0.04) and women (P < 0.001) had significantly better awareness about KC. Knowledge about KC mainly came from friends and reading about it. The mass media and social media were rarely used to seek knowledge. <strong>Conclusions:</strong> Awareness about the presentation, causes and management of KC was good in two-thirds of adults but with some variation. Strategies to involve the community and stress health education need to be urgently implemented. Campaigns should target the male and semi-urban population in western Saudi Arabia.