At the fuzzy front end of innovation emerging ideas are often fuzzy as well. This may lead to premature rejection of those early ideas and hence result in missed business opportunities. This paper introduces the Idea Arc-a canvas-based innovation tool that facilitates team-based discussions, elaboration and refinement of an idea, identification of missing parts, detection and correction of inconsistencies, finding fit between elements, and preparation for prototyping. We developed the canvas based on expert interviews and tested it in two workshops. As a result, this paper contributes to the existing research on the fuzzy front end of innovation and also informs the emerging research on visual innovation tools.@en