This article examines digital activism on Twitter against gender-based violence with regard to the March 8, 2017, feminist movement in Spain (8M). We explore a sample of 20,000 messages (tweets, retweets, and mentions) of the most commonly utilized hashtags in this context, such as #8M and # NiUnaMenos (Not one less [woman]). We analyze if, in the case of 8M in Spain, digital feminist activism constituted a challenge to the hegemonic frames of representation of gender-based violence. Using the concept of “ethical testimony,”, we demonstrate the opportunity that giving testimony on gender-based violence offers to digital feminist activism to act in an effective, political manner on Twitter, circumventing invisibility. These hashtags do not form strong conversational communities but rather serve to diffuse messages at a mass scale. Within these conversational communities, the term “victim” is rarely utilized, which we interpret as an accomplishment of women as agents capable of resisting their position of vulnerability.