This article surveys the evolving landscape of freedom of religion or belief (FoRB) measurement, proposing a typology of four major instrument types: narrative-coded datasets, expert opinion-based indices, survey-based tools, and real-time event datasets. While FoRB metrics have grown increasingly sophisticated, they still face challenges, including conceptual ambiguities, underreporting, and limited subnational sensitivity. The paper critiques existing tools in capturing non-Western religious expressions, intra-group diversity, and the distinction between restrictions and violations. It also highlights emerging priorities: measuring the positive presence of FoRB, ensuring equality in practice, and recognizing geographic variation. The study argues for a more holistic, context-sensitive, and policy-relevant approach.
