BACKGROUND: Measuring factors influencing time to presentation is important in developing and evaluating interventions to promote timely cancer diagnosis, yet there is a lack of validated, culturally relevant measurement tools. This study aimed to develop and validate the African Women Awareness of CANcer (AWACAN) tool to measure awareness of breast and cervical cancer in Sub-Saharan Africa (SSA). METHODS: Development of the AWACAN tool followed 4 steps: 1) Item generation based on existing measures and relevant literature. 2) Refinement of items via assessment of content and face validity using cancer experts' ratings and think aloud interviews with community participants in Uganda and South Africa. 3) Administration of the tool to community participants, university staff and cancer experts for assessment of validity using test-retest reliability (using Intra-Class Correlation (ICC) and adjusted Kappa coefficients), construct validity (comparing expert and community participant responses using t-tests) and internal reliability (using the Kuder-Richarson (KR-20) coefficient). 4) Translation of the final AWACAN tool into isiXhosa and Acholi. RESULTS: ICC scores indicated good test-retest reliability (≥ 0.7) for all breast cancer knowledge domains and cervical cancer risk factor and lay belief domains. Experts had higher knowledge of breast cancer risk factors (p < 0.001), and cervical cancer risk factors (p = 0.003) and symptoms (p = 0.001) than community participants, but similar knowledge of breast cancer symptoms (p = 0.066). Internal reliability for breast cancer risk factors, lay beliefs and symptom and cervical cancer symptom subscales was good with KR-20 values > 0.7, and lower (0.6) for the cervical cancer risk subscale. CONCLUSION: The final AWACAN tool includes items on socio-demographic details; breast and cervical cancer symptom awareness, risk factor awareness, lay beliefs, anticipated help-seeking behaviour; and barriers to seeking care. The tools showed evidence of content, face, construct and internal validity and test-retrest reliability and are available for use in SSA in three languages.