An international standard for the representation of dates and times in a consistent, unambiguous format.
ISO 8601 defines clear numeric representations of dates, times, and durations, making it possible to exchange data consistently across languages, regions, and systems.
It resolves regional ambiguities in formats. For instance, whether 03/05/2025 refers to March 5 or May 3 by prescribing a universal way to write dates, times, and intervals.
The standard is widely applied in computing, localization, databases, and international business processes. A common example is the YYYY-MM-DD format (2025-08-23), which avoids errors in data handling. ISO 8601 also specifies time (hh:mm:ss), time zones (Z for UTC or ±hh:mm for offsets), and combined date-time formats (2025-08-23T15:30:00Z).
ISO 8601 is intended for developers, database architects, localization professionals, system integrators, and organizations working across multiple regions. It plays a key role in APIs, financial platforms, translation workflows, and applications where accurate handling of dates and times is critical.
The standard removes confusion caused by regional differences and reduces the risk of costly data errors. It provides a single, reliable framework for representing time-related information, which supports global interoperability and simplifies internationalization and localization of digital products.
YYYY-MM-DD) and times (hh:mm:ss).YYYY-MM-DDThh:mm:ssZ).Z) and timezone offsets (±hh:mm).P3Y6M4DT12H30M5S).Note: The most recent editions are ISO 8601-1:2019 (Date and time — Basic rules) and ISO 8601-2:2019 (Extensions), which replaced earlier versions of the standard. A new edition, ISO/AWI 8601-1, is currently under development and will update the 2019 version once finalized. Since ISO standards evolve, always consult the official ISO catalogue entry for the latest status.