The Covid-19 pandemic has fuelled indignation. People have been indignant about the breaking of lockdown rules, about the mistakes and deficiencies of government pandemic policies, about enforced mask-wearing, about vaccination programmes (or lack thereof), about lack of care with regards vulnerable individuals, and more. Indeed, indignation seems to have been particularly prevalent on social media platforms such as Twitter and Facebook, where indignant remarks are often accompanied by variations on the hashtag #WTF?! In this paper, I explore indignation’s distinctive character as a form of moral anger, in particular suggesting that what is characteristic of indignation is not only that it discloses moral injustices but betrays our disbelief at the very occurrence of the offence. Having outlined the character of indignation, I consider how the structure of indignation impacts how we do, respond to, and receive indignation. I explore indignation in action, so to speak, in the context of Covid-19, with a particular emphasis on how indignation occurs ‘on the internet’.