Objective: To gather preliminary qualitative data that will assist in the codesign and development of a new informational and supportive website to assist informal cancer carers in Australia. Methods: Utilising a previously tested codesign process, informal carers' experiences and perspectives, including those of healthcare professionals', were examined via focus groups and/or interviews. Data were analysed via thematic analysis. Participants Rural (n=9) and urban (n=11) carers', and healthcare professionals' (n=8) perspectives were collected. Carers participated in a focus group (n=9) or telephone interview (n=11). Healthcare professionals completed an interview (n=6) or online survey (n=2). Results: Rural and urban carers typically felt ill prepared for their multitudinal caregiving responsibilities. Supporting patient-to-healthcare professional liaisons could especially challenge. Carers' biopsychosocial and fiscal strains were affected by patients' hardships and available informal supports. Rural carers described greater social support than urban carers. Both rural and urban carers also described discontentment related to a carer neglecting healthcare system. Both carers and healthcare professionals endorsed the need for a user-friendly, carer-specific website encompassing practical information and resources, peer-driven advice and evidence-based illness information, tailored to the Australian context. Conclusions: Carers and healthcare professionals recognise the pressing need for an Australian, cancer carer-specific online resource. Findings will inform the next phase, where a resource will be designed, developed and tested.