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Ballot Definition Common Data Format Specification



Benjamin Long, John Dziurłaj


This publication describes a ballot definition common data format for the interchange of logical and physical ballot style information. It contains a UML (Unified Modeling Language) model of the election data and a JSON (JavaScript Object Notation) and XML (eXtensible Markup Language) format derived from the UML model. It contains background information regarding how geopolitical geography is structured and used in the model and schemas. It also provides usage examples for anticipated use-cases. The format is comprehensive and at the same time very flexible, able to accommodate election scenarios used throughout the U.S. It is part of a series of common data format specifications for voting equipment.
Special Publication (NIST SP) - 1500-20
Report Number


Common data format (CDF), ballot definition (BD), ballot style, JavaScript Object Notation (JSON), unified markup language (UML), eXtensible Markup Language (XML).


Long, B. and Dziurłaj, J. (2023), Ballot Definition Common Data Format Specification, Special Publication (NIST SP), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed May 25, 2024)


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Created January 24, 2023