The dramatic rise of charitable crowdfunding has changed the landscape of fundraising and giving. Little empirical work, however, has been done to explore critical factors that are associated with successful charitable crowdfunding campaigns run both by formal charities and non-charities. To advance the literature on donation-based charitable crowdfunding, we draw on a unique dataset of 427 COVID-19 crowdfunding campaigns in China, examining whether and how external and internal quality signals are related to crowdfunding success measured by total donation amount. Our results show that crowdfunding success is positively associated with internal signals (updates and predefined duration), whereas the role of external signals (platform and award) is less certain. While we find a positive relationship between award information and funding success, informal campaigns using an alternative medium seem to generate more donations than formal campaigns using authorized platforms. The implications of this study for theory, practice and policy are also discussed.