ISO 8601-2:2019
Date and time — Representations for information interchange — Part 2: Extensions
This document specifies additional representations of dates of the Gregorian calendar and times based on the 24-hour clock that extend the basic rules and composite elements of those defined in ISO 8601-1. These representations are specified as character strings for use in information interchange. It is also applicable for representing times and time shifts based on Coordinated Universal Time (UTC).
These extensions include:
— uncertain or approximate dates, or dates with portions unspecified;
— extended time intervals;
— divisions of a year;
— sets and choices of calendar dates;
— grouped time scale units;
— repeat rules for recurring time intervals; and
— date and time arithmetic.
This document excludes the representation of date elements from non-Gregorian calendars, or times not from the 24-hour clock. This document does not address character encoding of representations specified in this document.
| Get this standard | Prices exclude GST | |
|---|---|---|
| PDF ( Single user document) |
$386.00 NZD
|
|
| HardCopy |
$430.00 NZD
|
|
| Networkable PDF |
Price varies
|
Foreword
Introduction
1 Scope
2 Normative references
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
3.1.1 Basic concepts
3.1.2 Feature description
3.1.3 Seasons
3.2 Symbols and abbreviated terms
3.2.1 General
3.2.2 Time scale component symbols
3.2.3 Composite component symbols
3.2.4 Symbols used to represent time scale component features
3.2.5 Symbols used in date and time representations
3.2.6 Designator symbols used in date and time expressions
3.2.7 Component symbols, representations and expressions
4 Extensions to time scale components and units
4.1 General
4.2 Order of time scale units
4.3 Additional explicit forms
4.3.1 General
4.3.2 Value prefixing
4.3.3 Calendar day of week
4.3.4 Calendar day of year
4.3.5 Decade
4.3.6 Century
4.4 Numerical extensions
4.4.1 Negative values
4.4.2 Exponential values
4.4.3 Significant digits
4.5 Qualification of uncertainty and approximation
4.6 Unspecified digits
4.6.1 General
4.6.2 Unspecified time component value in explicit forms
4.6.3 Unspecified time component digits in implicit forms
4.7 Expanded calendar year
4.7.1 General
4.7.2 Letter-prefixed calendar year
4.7.3 Exponential calendar year
4.7.4 Significant digits
4.8 Sub-year groupings
4.8.1 Listing of seasons and common sub-year groupings
4.8.2 Groupings represented as time scale components
4.8.3 Groupings represented as months
5 Grouped time scale units
5.1 General
5.2 Unit definition
5.3 Unit value
5.4 Application within representations
5.4.1 General
5.4.2 Use of grouped units
5.4.3 Adherence to grouped unit boundaries
5.4.4 Representation with time shift
5.4.5 Conversion to basic time scale units
6 Set representation
6.1 Set of date and time expressions
6.2 Single element amongst set
6.3 Range element expansion
6.4 Set representations and expansion
6.5 Expressions with time scale components
6.6 Integer expressions
7 Explicit representation for date and time
7.1 General
7.2 Date
7.2.1 General
7.2.2 Calendar date
7.2.3 Ordinal date
7.2.4 Week date
7.3 Time of day
7.3.1 Local time of day
7.3.2 Beginning of the day
7.4 Time shift
7.5 Date with shift
7.6 Time of day with time shift
7.7 Date and time of day
7.7.1 General
7.7.2 Date and time only
7.7.3 Date and time with shift
7.8 Decade
7.9 Century
7.10 Omission of zero-valued components
7.11 Indication of precision
7.12 Decimal fractions for time
7.13 Representations other than complete
7.14 Time intervals
7.14.1 General
7.14.2 Time scale component order
7.14.3 Time shift indication
7.15 Recurring time intervals
8 Qualification of date and time expressions
8.1 General
8.2 Principles
8.2.1 Complete qualification
8.2.2 Group qualification
8.2.3 Individual qualification
8.2.4 Preferred representations for resolving ambiguity
8.3 Time scale components allowing qualification
8.3.1 General
8.3.2 Calendar year, left qualified:
8.3.3 Calendar month, left qualified
8.3.4 Calendar week of year, left qualified
8.3.5 Calendar day of month, left qualified
8.3.6 Calendar day of week, left qualified
8.3.7 Calendar day of year, left qualified
8.3.8 Clock hour, left qualified
8.3.9 Clock minute, left qualified
8.3.10 Clock second, left qualified
8.3.11 Decade, left qualified
8.3.12 Century, left qualified
8.4 Calendar date representations with qualification
8.4.1 Complete representation of a calendar date
8.4.2 Representations of calendar dates with reduced precision
8.4.3 Expanded representations of calendar dates
8.4.4 Qualification of a group of time scale components from the right
8.4.5 Qualification of individual time scale components
8.4.6 Allowing group and individual qualifications of time scale components
8.5 Date and time expressions with qualification
9 Unspecified digits
9.1 General
9.2 Calendar date representations with unspecified digits
9.2.1 Unspecified time scale component values from the right
9.2.2 Unspecified digit anywhere in time scale component
9.3 Date and time expressions with unspecified digits
10 Extended time interval representations
10.1 General
10.2 Unknown or open start or end time intervals
10.3 Qualification of dates in time intervals
10.3.1 General
10.3.2 Complete qualification
10.3.3 Partial qualification
10.4 Unspecified portions of dates in time intervals
10.5 Uncertain and approximate dates in unknown or open time intervals
10.6 Before and after with qualified time scale components
11 Explicit duration and extensions
11.1 General
11.2 Durational units
11.3 Representations
11.3.1 General
11.3.2 Composite representation
11.3.3 Precedence representation
11.4 Fractional duration
12 Selection of date and time
12.1 General
12.2 Selection rules
12.2.1 Selection of calendar month of year
12.2.2 Selection of calendar week of year
12.3 Selection of calendar day of month
12.4 Selection of week days
12.5 Selection of ordinal days in calendar year
12.6 Selection of hours
12.7 Selection of minutes
12.8 Selection of seconds
12.9 Selection of position
12.10 Selection with time interval
12.11 Application within representations
12.11.1 General
12.11.2 Context set by selection
12.11.3 Within time intervals
13 Recurring time intervals with repeat rules
13.1 General
13.2 Method of specification
13.3 Specification of time interval
13.4 Repeat rule
13.4.1 General
13.4.2 Eligibility part and eligible time intervals
13.4.3 Selection part and selection rules
13.5 Representations
13.6 Evaluation of a repeat rule
13.6.1 General
13.6.2 Time scale unit precision
13.6.3 Inheritance of component values from time interval start
14 Date and time arithmetic
14.1 General
14.2 Addition and subtraction
14.3 Multiplication
14.4 Date time modified by duration
15 Profiles
15.1 General
15.2 Requirements
Annex A (informative) Profile: Extended Date/Time Format
Annex B (informative) Interactions between eligible time intervals with the selection part
Annex C (informative) Compatibility considerations of repeat rules with IETF RFC 5545 recurrences
Annex D (informative) Evaluation of date time formulas and duration considerations
Bibliography
Keep me up-to-date
Sign up to receive updates when there are changes to this standard
Related Information
Similar Standards
-
AS/NZS 2632.1:2020
Codes for the representation of names of countries and their subdivisions, Part 1: Country code -
AS/NZS 2632.2:2020
Codes for the representation of names of countries and their subdivisions, Part 2: Country subdivision code -
AS/NZS 2632.3:2020
Codes for the representation of names of countries and their subdivisions, Part 3: Code for formerly used names of countries -
AS/NZS ISO 8601.1:2021
Date and time - Representations for information interchange, Part 1: Basic rules
Foreword
Introduction
1 Scope
2 Normative references
3 Terms, definitions, symbols and abbreviated terms
3.1 Terms and definitions
3.1.1 Basic concepts
3.1.2 Feature description
3.1.3 Seasons
3.2 Symbols and abbreviated terms
3.2.1 General
3.2.2 Time scale component symbols
3.2.3 Composite component symbols
3.2.4 Symbols used to represent time scale component features
3.2.5 Symbols used in date and time representations
3.2.6 Designator symbols used in date and time expressions
3.2.7 Component symbols, representations and expressions
4 Extensions to time scale components and units
4.1 General
4.2 Order of time scale units
4.3 Additional explicit forms
4.3.1 General
4.3.2 Value prefixing
4.3.3 Calendar day of week
4.3.4 Calendar day of year
4.3.5 Decade
4.3.6 Century
4.4 Numerical extensions
4.4.1 Negative values
4.4.2 Exponential values
4.4.3 Significant digits
4.5 Qualification of uncertainty and approximation
4.6 Unspecified digits
4.6.1 General
4.6.2 Unspecified time component value in explicit forms
4.6.3 Unspecified time component digits in implicit forms
4.7 Expanded calendar year
4.7.1 General
4.7.2 Letter-prefixed calendar year
4.7.3 Exponential calendar year
4.7.4 Significant digits
4.8 Sub-year groupings
4.8.1 Listing of seasons and common sub-year groupings
4.8.2 Groupings represented as time scale components
4.8.3 Groupings represented as months
5 Grouped time scale units
5.1 General
5.2 Unit definition
5.3 Unit value
5.4 Application within representations
5.4.1 General
5.4.2 Use of grouped units
5.4.3 Adherence to grouped unit boundaries
5.4.4 Representation with time shift
5.4.5 Conversion to basic time scale units
6 Set representation
6.1 Set of date and time expressions
6.2 Single element amongst set
6.3 Range element expansion
6.4 Set representations and expansion
6.5 Expressions with time scale components
6.6 Integer expressions
7 Explicit representation for date and time
7.1 General
7.2 Date
7.2.1 General
7.2.2 Calendar date
7.2.3 Ordinal date
7.2.4 Week date
7.3 Time of day
7.3.1 Local time of day
7.3.2 Beginning of the day
7.4 Time shift
7.5 Date with shift
7.6 Time of day with time shift
7.7 Date and time of day
7.7.1 General
7.7.2 Date and time only
7.7.3 Date and time with shift
7.8 Decade
7.9 Century
7.10 Omission of zero-valued components
7.11 Indication of precision
7.12 Decimal fractions for time
7.13 Representations other than complete
7.14 Time intervals
7.14.1 General
7.14.2 Time scale component order
7.14.3 Time shift indication
7.15 Recurring time intervals
8 Qualification of date and time expressions
8.1 General
8.2 Principles
8.2.1 Complete qualification
8.2.2 Group qualification
8.2.3 Individual qualification
8.2.4 Preferred representations for resolving ambiguity
8.3 Time scale components allowing qualification
8.3.1 General
8.3.2 Calendar year, left qualified:
8.3.3 Calendar month, left qualified
8.3.4 Calendar week of year, left qualified
8.3.5 Calendar day of month, left qualified
8.3.6 Calendar day of week, left qualified
8.3.7 Calendar day of year, left qualified
8.3.8 Clock hour, left qualified
8.3.9 Clock minute, left qualified
8.3.10 Clock second, left qualified
8.3.11 Decade, left qualified
8.3.12 Century, left qualified
8.4 Calendar date representations with qualification
8.4.1 Complete representation of a calendar date
8.4.2 Representations of calendar dates with reduced precision
8.4.3 Expanded representations of calendar dates
8.4.4 Qualification of a group of time scale components from the right
8.4.5 Qualification of individual time scale components
8.4.6 Allowing group and individual qualifications of time scale components
8.5 Date and time expressions with qualification
9 Unspecified digits
9.1 General
9.2 Calendar date representations with unspecified digits
9.2.1 Unspecified time scale component values from the right
9.2.2 Unspecified digit anywhere in time scale component
9.3 Date and time expressions with unspecified digits
10 Extended time interval representations
10.1 General
10.2 Unknown or open start or end time intervals
10.3 Qualification of dates in time intervals
10.3.1 General
10.3.2 Complete qualification
10.3.3 Partial qualification
10.4 Unspecified portions of dates in time intervals
10.5 Uncertain and approximate dates in unknown or open time intervals
10.6 Before and after with qualified time scale components
11 Explicit duration and extensions
11.1 General
11.2 Durational units
11.3 Representations
11.3.1 General
11.3.2 Composite representation
11.3.3 Precedence representation
11.4 Fractional duration
12 Selection of date and time
12.1 General
12.2 Selection rules
12.2.1 Selection of calendar month of year
12.2.2 Selection of calendar week of year
12.3 Selection of calendar day of month
12.4 Selection of week days
12.5 Selection of ordinal days in calendar year
12.6 Selection of hours
12.7 Selection of minutes
12.8 Selection of seconds
12.9 Selection of position
12.10 Selection with time interval
12.11 Application within representations
12.11.1 General
12.11.2 Context set by selection
12.11.3 Within time intervals
13 Recurring time intervals with repeat rules
13.1 General
13.2 Method of specification
13.3 Specification of time interval
13.4 Repeat rule
13.4.1 General
13.4.2 Eligibility part and eligible time intervals
13.4.3 Selection part and selection rules
13.5 Representations
13.6 Evaluation of a repeat rule
13.6.1 General
13.6.2 Time scale unit precision
13.6.3 Inheritance of component values from time interval start
14 Date and time arithmetic
14.1 General
14.2 Addition and subtraction
14.3 Multiplication
14.4 Date time modified by duration
15 Profiles
15.1 General
15.2 Requirements
Annex A (informative) Profile: Extended Date/Time Format
Annex B (informative) Interactions between eligible time intervals with the selection part
Annex C (informative) Compatibility considerations of repeat rules with IETF RFC 5545 recurrences
Annex D (informative) Evaluation of date time formulas and duration considerations
Bibliography