‘Common but Differentiated Responsibilities and Respective Capabilities’ (CBDR-RC) is a core principle in the United Nations Framework Convention on Climate Change (UNFCCC) used to operationalize equity, but it could be defined in many ways. To date, the bulk of attention has been on the first part of this principle – CBDR – because of the importance of addressing responsibility. However, we propose that a more robust notion of RC is possible, useful and timely as countries are currently articulating their first Nationally Determined Contributions, a process that is expected to ratchet up over time under the new regime. We combine Sen and Nussbaum's notion of a ‘capabilities approach’ with the framework provided by the UNFCCC to identify five sub-elements of RC and propose metrics for each of them. These sub-elements are human development, economic capacity, resilience to climate impacts, governance capacity, and technical and innovation capacity. We are not proposing replacing discussions of responsibility with those of capabilities. Responsibility remains central to the climate equity discussion. However, differentiation based on responsibility alone may not be adequate to address climate impacts or human development needs, both of which are central to climate equity. Providing countries with a robust approach for articulating RC enhances the overall ability for the principle of CBDR-RC to address the trio of climate equity challenges posed by unequal climate impacts, development status, and responsibility. Moreover, including a more robust notion of capabilities in the operationalization of equity may identify additional means for supporting specific domestic climate policies able to address core development needs in the context of increased carbon constraints and climate impacts.