The global development of the offshore renewable energy sector has been driven by extensive investment and research in the utilization of offshore renewable energies, mainly at the regional level. However, for mid to long-term marine energy development planning, a comprehensive assessment of the global potential for the exploitation of the main offshore resources is required. This work developed and implemented an innovative methodological approach to identify potential zones for wind and wave energy exploitation at the global level, using long-term data series with fine spatial and temporal resolution. The proposed methodology was based on a five-step approach comprised of: (i) a resource assessment, to identify the zones with favorable conditions for energy exploitation; (ii) a structural survivability assessment, to identify feasible areas which would likely ensure the integrity and durability of the wind and wave devices; (iii) a logistics assessment, to evaluate the possibility of carrying out installation, operations, and maintenance activities; (iv) an assessment of the distance to consumer centers, to estimate the feasibility of transmission to the main urban areas; and (v) an estimate of the extractable power of the identified potential zones. For wind power, the United Kingdom (with 1470 TWh/month using a 10-MW turbine) and the United States (1079 TWh/month) were the countries with the highest estimated energy output of the identified potential zones. For wave energy, Brazil and New Zealand presented good opportunities for the development of the wave energy industry, with an estimated extractable power of 372 TWh/month and 286 TWh/month, respectively. The unique preliminary global analysis presented in this work provides guidelines to assist in the development of wave and offshore wind industries, in addition to supporting the management of marine spaces. Moreover, the methodologies can be replicated for other marine activities.