We present an application programming interface (API) which facilitates public access to a global relational database of earthquake ground motion intensity measures, associated metadata, and time-series data. Next Generation Attenuation (NGA)-East and NGA-West2 project spreadsheets have been adapted into a relational database format composed of multiple tables through a series of primary and foreign keys. The combined dataset has been expanded to include contributions from earthquakes, generally with magnitudes greater than M3.9, that have occurred since the conclusion of the data synthesis component of both projects in 2011. Currently the database includes 62,449 ground motions recorded at 9,092 stations for 899 events. The database is accessible through an API, which allows users to interact with and query the database directly without detailed knowledge of structure query language (SQL). Simple queries are constructed by appending relatively straightforward query string parameters to the end of a uniform resource location (URL) that serves as an endpoint, which returns only data that satisfy the query constraints. The web-served nature of the database means that users have immediate access to ground motion data as soon as it is collected, reviewed, and uploaded. Furthermore, integrated end-to-end workflows – which do not require files to be downloaded and saved in local memory – are possible through the API. The structure of the database has been designed to accommodate growth, with ongoing efforts to integrate global ground motion data in anticipation of the NGA-West3 project, and improve ease-of access through the API.