An event is a geographically and temporally focused 'nonroutine, collective and public' action aimed at making broad social or political claims (Olzak, 1989, p. 124). Event attendance matters for how the event is perceived and reported on by citizens, the media and political leaders (Biggs, 2018;McPhail & McCarthy, 2004). Scholars of Indian politics have measured event size with proxies: using deaths, injuries, or the number of First Information Reports (FIRs) filed to quantify riot size and relying on newspaper-based estimates of the size of other collective action events (Bhavnani & Lacina, 2015;Varshney & Wilkinson, 1996). Is there a way to improve our event size estimates in order to more effectively study this critical indicator of event success and impact?Political scientists have recently developed methods for detecting event size using data from technology-based sources, including geolocation, social media activity and social media photos. In some contexts, these methods comport well with existing newspaper-based measures of event size, and their automated nature reduces cost and eases implementation compared to traditional newspaper searches (Botta et al., 2015).In this note, I apply technology-based event size measures to Indian events. I argue that the way that events develop in India makes using technology-based data to estimate event size particularly difficult. I take as my case the 2019 and 2020 protests surrounding the Citizenship Amendment Act (CAA) and related causes in Delhi. These protests were highly publicized, politicized and contested, with public campaigns waged on social media. Drawing on fieldwork at key protest sites, a review of social media data and media reports, I find that strategic choices on behalf of both protesters and the government made estimating event size using technological data quite challenging. I then discuss some ways that event size measurement techniques can be adapted for the Indian context.