Abstract Introduction Health literacy, as the ability to obtain, process and understand health information, including gender and sexuality awareness, appears to be underdeveloped in terms of measurement tools and thematic materials. The literature indicates the existence of serious deficits in gender and sexual health literacy at all levels, with implications for relationships with citizens and patients. Methods Delphi study agreement was conducted and a pool of potential scale items was generated, reflecting a range of skills and abilities within each domain. Items were carefully worded to ensure clarity, cultural sensitivity and relevance to different gender identities and sexual orientations. Expert review and cognitive pre-testing were employed to refine item wording, assess content validity, and ensure that the 10-item scale was comprehensible and relevant to the target population. Results The theoretical development of the 10-item Digital Health Gender and Sexual Health Literacy Scale was successfully completed. The scale items were designed to provide a comprehensive measure of an individual’s ability to navigate the digital landscape for gender and sexual health information. Conclusions The theoretical validation of the Digital Health Gender and Sexual Health Literacy Scale (DiGeSHeL) provides the community with a promising tool to assess individuals’ confidence and ability to use digital technologies for sexual health information and resources. However, further research is needed to validate the scale and test its reliability with a diverse group of participants. Once validated, this scale could be a valuable tool for sexual health promotion programmes to identify gaps and evaluate the impact of digital literacy interventions. Key messages • Gender and sexual literacy are crucial for health. • Health literacy as six vital sign.