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CalConnect establishes TC UNITS, adopts UnitsML ​

The Calendaring and Scheduling Consortium (CalConnect) has announced the establishment of its Technical Committee on Units of Measure — TC UNITS — and the adoption of UnitsML as the authoritative mechanism for encoding scientific units of measure.

Why a Technical Committee for units ​

Units and their representations form the basis of measurements, critical to everything from timekeeping and trade to manufacturing and mission-critical operations. Despite the universal importance of units, there has been no single authoritative mechanism for representing them unambiguously in digital systems.

TC UNITS is chartered to change that. Its scope includes:

  • Standardization of a comprehensive data model for units representation
  • Multiple serialization formats including XML (UnitsML), JSON, and YAML
  • The authoritative UnitsDB register — a structured database of units, quantities, dimensions, prefixes, scales, and unit systems
  • Integration guidelines with existing technologies such as MathML
  • Development and maintenance of the UnitsML official website

International collaboration ​

A key objective of TC UNITS is to pursue international standardization through ISO and IEC, while working closely with the International Bureau of Weights and Measures (BIPM) towards an interoperable "Digital SI" infrastructure.

As Mike Douglass, Executive Director of CalConnect, stated:

"Our collaboration with ISO, IEC, and BIPM will ensure UnitsML becomes a globally recognized standard for digital unit representation."

Leadership ​

The committee is led by co-chairs Karen Olsen and Nick Nicholas, who bring deep expertise in standards development and scientific unit representation.

What this means for UnitsML ​

The establishment of TC UNITS marks a significant milestone for UnitsML. Under CalConnect's governance, UnitsML gains:

  • Formal standards process — structured development and publication of UnitsML specifications
  • International alignment — coordination with ISO, IEC, and BIPM ensures global interoperability
  • Long-term maintenance — a standing committee ensures ongoing development and community engagement

Established in September 2022 as a standing committee, TC UNITS represents a significant step forward in the standardization of scientific unit representation while pursuing broader international adoption.

Learn more ​