Online incentive mechanisms constitute a strategy to stimulate members to participate and perform tasks in virtual communities. Given the diversity of variables and particularities that define virtual communities and their contexts, it is a challenge to identify and define incentives that are adequate to a given community. Our focus is on providing a systematic way to help designers to reason and develop their own analysis. We propose a conceptual framework to support the analysis of virtual communities, aiming to facilitate the definition of online incentive mechanisms. The framework is presented as a canvas with issues to be addressed through a set of questions, offering a visual and understandable guide. We evaluated the framework with a case study. We found that the framework satisfactorily supports designers in defining more complete and effective online incentive mechanisms.