Background <p>Adolescents and young adults with type 1 diabetes face unique challenges in self-management, particularly during the transition to adult care. Although digital tools are available to enhance self-management, they often lack grounding in behavior change theory and fail to fully engage youth in sustained behavior change. This study aimed to address this gap by developing a behavior change-informed design process for creating online educational technology tailored to youth with type 1 diabetes.</p> Methods <p>A combined inductive and deductive qualitative analysis was conducted on eight focus group discussions with youth aged 14 to 24 years and healthcare professionals (<i>n</i> = 30) to identify self-management needs and corresponding content and features.</p> Results <p>Key needs included personalized education, improved diabetes understanding, community connection, collaborative learning, and confidence-building. These were mapped using the Behavior Change Wheel and translated into four design axes: (1) Self-paced learning with tailored topic suggestions and question-and-answer formats; (2) Youth empowerment: through testimonials, discussion forums, and shareable content; (3) Confidential access to peer-reviewed information on sensitive topics; and (4) Support for applying Diabetes knowledge in daily life through real-life scenarios with feedback on topics such as mental health, finances, sexual health, and eating disorders.</p> Conclusion <p>Grounded in behavioral theory and the real-life experiences of youth with type 1 diabetes, these four design axes offer a framework for developing digital education tools that effectively engage and support diabetes self-management.</p>