railML.org is a non-profit association that develops and maintains railML®, an open XML-based data exchange standard for the railway sector. Founded on 24 April 2002, the initiative was created to address a practical problem: railway software systems often need to exchange timetable, infrastructure and rolling stock data, but historically use different formats and interfaces. railML.org’s answer is a shared, XML-based language intended to make that exchange more consistent and less ambiguous.
The organisation is based in Dresden, Germany, where its administrative operations are centralised. It is registered as an association under German law and describes itself as independent of railways, manufacturers and public authorities. Its work is rooted in collaboration: railML is developed with input from interested institutions and businesses across Europe and beyond, and the standard is available for use under license conditions that allow free access to the schemas for data exchange.
railML.org’s main activities include the development of schema versions, documentation, example data and validation tools. One of its better-known tools is railVIVID, which lets users view and validate railML files without needing deep XML expertise. The organisation also supports implementation in practice, for example through workshops, technical discussions and cooperation with sector bodies.
In 2022, railML was established as ISO/TS 4398 under the name RailDax, extending its relevance beyond the original community. More recently, railML.org has been involved in the IDX4rail project and in work to map railML 3.3 data to the EU’s TAF/TAP TSI messaging standard, showing its role in the wider effort to standardise railway data exchange.