ISO/TC 154

WG 5 working group

Date and time

WG 5 provides a common platform for all date and time stakeholders, to enable a unified, interoperable of date and time across populations and systems. It publishes the ISO 8601 family of standards in ubiquitous use today.

Collaborative parties


CalConnect, the Calendaring and Scheduling Consortium, is a Category A liaison of ISO/TC 154.

CalConnect is focused on the interoperable exchange of calendaring and scheduling information between dissimilar programs, platforms, and technologies. Our mission is to promote general understanding of and provide mechanisms to allow interoperable calendaring and scheduling methodologies, tools and applications to enter the mainstream of computing.

CalConnect’s TC DATETIME is heavily engaged with all WG 5 projects, including its contribution to ISO 8601-2.

Current collaborative projects include:


ITU is a Category A liaison with ISO/TC 154, with specific interest in the activities of WG 5.

From its inception in 1865, ITU-T has driven a contribution-led, consensus-based approach to standards development in which all countries and companies, no matter how large or small, are afforded equal rights to influence the development of ITU-T Recommendations. From its beginnings as a body standardizing international telegraph exchange, through its formative role in telecommunications, and in today’s converged ICT ecosystem, ITU-T has provided the world’s best facilities to the global standardization community and remains the world’s only truly global ICT standards body.

ITU-T is the standardization arm of ITU, the United Nations specialized agency for information and communication technologies – ICTs.


WG 5 was established to manage ISO 8601, the international date time standard.

Previous leadership

Ray Denenberg

ISO/TC 46, Liaison past convenor since 2018/01/01 until 2019/04/01