At first sight, child well-being and international children’s rights law have much in common. Specifically, they both focus on a category of human beings defined by age (children), and both are concerned about ‘child flourishing’. Surprisingly perhaps, the word well-being is rarely used in children’s rights work, and it is not very prominent in the leading human rights instrument on children’s rights, the Convention on the Rights of the Child. In this paper, I pursue two objectives. First, I want to find out how the notion of child well-being has been constructed in international children’s rights and which proxies in the latter can help to imbue the concept with meaning. Second, I explore whether and how the fields of children’s rights law and child well-being may engage in a fruitful dialogue. I challenge the view that children’s rights are unable to offer more than a minimalistic checklist for child well-being, identify learning points for children’s rights, and propose speaking points for a sustained dialogue between the two fields.