CalendarDate

A CalendarDate represents a date without any time components in a specific calendar system.

install	`yarn add @internationalized/date`
version	3.0.1
usage	`import {CalendarDate} from '@internationalized/date'`

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Introduction#

A CalendarDate object represents a date without any time components, in a specific calendar system such as the Gregorian calendar. Use this type to represent dates where the time is not important, such as a birthday or an all day calendar event. If you need to refer to a specific time, use a CalendarDateTime or ZonedDateTime instead.

A CalendarDate can be created using the constructor. This example creates a date that represents February 3rd, 2022 in the Gregorian calendar system.

import {CalendarDate} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);

import {CalendarDate} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);

import {CalendarDate} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    3
  );

You can also create a CalendarDate by parsing an ISO 8601 formatted string using the parseDate function.

import {parseDate} from '@internationalized/date';

let date = parseDate('2022-02-03');

import {parseDate} from '@internationalized/date';

let date = parseDate('2022-02-03');

import {parseDate} from '@internationalized/date';

let date = parseDate(
  '2022-02-03'
);

Today's date can be retrieved using the today function. This requires a time zone identifier to be provided, which is used to determine the local date. The getLocalTimeZone function can be used to retrieve the user's current time zone.

import {today, getLocalTimeZone} from '@internationalized/date';

let nyDate = today('America/New_York');
let localDate = today(getLocalTimeZone());

import {
  getLocalTimeZone,
  today
} from '@internationalized/date';

let nyDate = today('America/New_York');
let localDate = today(getLocalTimeZone());

import {
  getLocalTimeZone,
  today
} from '@internationalized/date';

let nyDate = today(
  'America/New_York'
);
let localDate = today(
  getLocalTimeZone()
);

Once you have a CalendarDate object, you can read its properties, or manipulate it as described in the Manipulating dates section below. You can also convert it to an ISO 8601 string, native JavaScript Date object, or another representation. See the Conversion section below for details.

let date = new CalendarDate(2022, 2, 3);
date.toString(); // '2022-02-03'

let date = new CalendarDate(2022, 2, 3);
date.toString(); // '2022-02-03'

let date =
  new CalendarDate(
    2022,
    2,
    3
  );
date.toString(); // '2022-02-03'

Interface#

Properties

Name	Type	Description
`calendar`	`Calendar`	The calendar system associated with this date, e.g. Gregorian.
`era`	`string`	The calendar era for this date, e.g. "BC" or "AD".
`year`	`number`	The year of this date within the era.
`month`	`number`	The month number within the year. Note that some calendar systems such as Hebrew may have a variable number of months per year. Therefore, month numbers may not always correspond to the same month names in different years.
`day`	`number`	The day number within the month.

Methods

Method	Description
`constructor( (...args: any[] )): void`
`copy(): CalendarDate`	Returns a copy of this date.
`add( (duration: DateDuration )): CalendarDate`	Returns a new `CalendarDate` with the given duration added to it.
`subtract( (duration: DateDuration )): CalendarDate`	Returns a new `CalendarDate` with the given duration subtracted from it.
`set( (fields: DateFields )): CalendarDate`	Returns a new `CalendarDate` with the given fields set to the provided values. Other fields will be constrained accordingly.
`cycle( field: DateField, amount: number, options?: CycleOptions ): CalendarDate`	Returns a new `CalendarDate` with the given field adjusted by a specified amount. When the resulting value reaches the limits of the field, it wraps around.
`toDate( (timeZone: string )): Date`	Converts the date to a native JavaScript Date object, with the time set to midnight in the given time zone.
`toString(): string`	Converts the date to an ISO 8601 formatted string.
`compare( (b: AnyCalendarDate )): number`	Compares this date with another. A negative result indicates that this date is before the given one, and a positive date indicates that it is after.

Calendar systems#

By default, CalendarDate uses the Gregorian calendar system, but many other calendar systems that are used around the world are supported, such as Hebrew, Indian, Islamic, Buddhist, Ethiopic, and more. A Calendar instance can be passed to the CalendarDate constructor to represent dates in that calendar system.

This example creates a date in the Buddhist calendar system, which is equivalent to April 4th, 2020 in the Gregorian calendar.

import {BuddhistCalendar} from '@internationalized/date';

let date = new CalendarDate(new BuddhistCalendar(), 2563, 4, 30);

import {BuddhistCalendar} from '@internationalized/date';

let date = new CalendarDate(
  new BuddhistCalendar(),
  2563,
  4,
  30
);

import {BuddhistCalendar} from '@internationalized/date';

let date =
  new CalendarDate(
    new BuddhistCalendar(),
    2563,
    4,
    30
  );

See the Calendar docs for details about the supported calendars.

Eras#

Many calendar systems have only one era, or a modern era and a pre-modern era (e.g. AD and BC in the Gregorian calendar). However, other calendar systems may have many eras. For example, the Japanese calendar has eras for the reign of each Emperor. CalendarDate represents eras using string identifiers, which can be passed as an additional parameter to the constructor before the year. When eras are present, years are numbered starting from 1 within the era.

This example creates a date in the Japanese calendar system, which is equivalent to April 4th, 2020 in the Gregorian calendar.

import {JapaneseCalendar} from '@internationalized/date';

let date = new CalendarDate(new JapaneseCalendar(), 'heisei', 31, 4, 30)

import {JapaneseCalendar} from '@internationalized/date';

let date = new CalendarDate(
  new JapaneseCalendar(),
  'heisei',
  31,
  4,
  30
);

import {JapaneseCalendar} from '@internationalized/date';

let date =
  new CalendarDate(
    new JapaneseCalendar(),
    'heisei',
    31,
    4,
    30
  );

A list of valid era identifiers can be retrieved using the getEras method of a Calendar instance. If an era is not provided, the date is assumed to be in the current era.

Converting between calendars#

The toCalendar function can be used to convert a date from one calendar system to another.

This example converts a Gregorian date to a Hebrew one.

import {toCalendar, HebrewCalendar} from '@internationalized/date';

let gregorianDate = new CalendarDate(2020, 9, 19);
let hebrewDate = toCalendar(gregorianDate, new HebrewCalendar());
// => new CalendarDate(new HebrewCalendar(), 5781, 1, 1)

import {
  HebrewCalendar,
  toCalendar
} from '@internationalized/date';

let gregorianDate = new CalendarDate(2020, 9, 19);
let hebrewDate = toCalendar(
  gregorianDate,
  new HebrewCalendar()
);
// => new CalendarDate(new HebrewCalendar(), 5781, 1, 1)

import {
  HebrewCalendar,
  toCalendar
} from '@internationalized/date';

let gregorianDate =
  new CalendarDate(
    2020,
    9,
    19
  );
let hebrewDate =
  toCalendar(
    gregorianDate,
    new HebrewCalendar()
  );
// => new CalendarDate(new HebrewCalendar(), 5781, 1, 1)

Manipulating dates#

Adding and subtracting durations#

A DateDuration is an object that represents an amount of time, with fields such as years, months, and days. The add and subtract methods of CalendarDate objects can be used to adjust the date by the given duration. These methods return a new date, and do not mutate the original.

let date = new CalendarDate(2022, 2, 3);

date.add({weeks: 1}); // 2022-02-10
date.add({months: 1}); // 2022-03-03
date.add({years: 1, months: 1, days: 1}); // 2023-03-04

date.subtract({weeks: 1}); // 2022-01-27
date.subtract({months: 1}); // 2022-01-03
date.subtract({years: 1, months: 1, days: 1}); // 2021-01-02

let date = new CalendarDate(2022, 2, 3);

date.add({weeks: 1}); // 2022-02-10
date.add({months: 1}); // 2022-03-03
date.add({years: 1, months: 1, days: 1}); // 2023-03-04

date.subtract({weeks: 1}); // 2022-01-27
date.subtract({months: 1}); // 2022-01-03
date.subtract({years: 1, months: 1, days: 1}); // 2021-01-02

let date =
  new CalendarDate(
    2022,
    2,
    3
  );

date.add({ weeks: 1 }); // 2022-02-10
date.add({ months: 1 }); // 2022-03-03
date.add({
  years: 1,
  months: 1,
  days: 1
}); // 2023-03-04

date.subtract({
  weeks: 1
}); // 2022-01-27
date.subtract({
  months: 1
}); // 2022-01-03
date.subtract({
  years: 1,
  months: 1,
  days: 1
}); // 2021-01-02

Adding or subtracting a duration that goes beyond the limits of a particular field will cause the date to be balanced. For example, adding one day to August 31st results in September 1st. In addition, if adding or subtracting one field causes another to be invalid, the date will be constrained. For example, adding one month to August 31st results in September 30th because September 31st does not exist.

Setting fields#

CalendarDate objects are immutable, which means their properties cannot be set directly. Instead, use the set method, and pass the fields to be modified. This will return a new CalendarDate with the updated values.

let date = new CalendarDate(2022, 2, 3);
date.set({day: 10}); // 2022-02-10
date.set({month: 5}); // 2022-05-03
date.set({year: 2023, month: 10, day: 16}); // 2023-10-16

let date = new CalendarDate(2022, 2, 3);
date.set({day: 10}); // 2022-02-10
date.set({month: 5}); // 2022-05-03
date.set({year: 2023, month: 10, day: 16}); // 2023-10-16

let date =
  new CalendarDate(
    2022,
    2,
    3
  );
date.set({ day: 10 }); // 2022-02-10
date.set({ month: 5 }); // 2022-05-03
date.set({
  year: 2023,
  month: 10,
  day: 16
}); // 2023-10-16

Setting a field to a value that is outside the valid range will cause it to be constrained. For example, setting the day to a value that is greater than the number of days in the month, will result in the last day of the month.

let date = new CalendarDate(2022, 2, 3);
date.set({day: 100}); // 2022-02-28
date.set({month: 20}); // 2022-12-03

let date = new CalendarDate(2022, 2, 3);
date.set({day: 100}); // 2022-02-28
date.set({month: 20}); // 2022-12-03

let date =
  new CalendarDate(
    2022,
    2,
    3
  );
date.set({ day: 100 }); // 2022-02-28
date.set({ month: 20 }); // 2022-12-03

Cycling fields#

The cycle method allows incrementing or decrementing a single field. It is similar to the add and subtract methods, but when the value reaches the minimum or maximum, it wraps around rather than affecting other fields.

let date = new CalendarDate(2022, 12, 31);
date.cycle('day', 1); // 2022-12-01
date.cycle('month', 1); // 2022-01-31

let date = new CalendarDate(2022, 1, 1);
date.cycle('day', -1); // 2022-01-31
date.cycle('month', -1); // 2022-12-01

let date = new CalendarDate(2022, 12, 31);
date.cycle('day', 1); // 2022-12-01
date.cycle('month', 1); // 2022-01-31

let date = new CalendarDate(2022, 1, 1);
date.cycle('day', -1); // 2022-01-31
date.cycle('month', -1); // 2022-12-01

let date =
  new CalendarDate(
    2022,
    12,
    31
  );
date.cycle('day', 1); // 2022-12-01
date.cycle('month', 1); // 2022-01-31

let date =
  new CalendarDate(
    2022,
    1,
    1
  );
date.cycle('day', -1); // 2022-01-31
date.cycle('month', -1); // 2022-12-01

The round option may also be passed, which causes the value to be rounded to increments of the given amount. For example, you could round the year to increments of 5.

let date = new CalendarDate(2022, 2, 3);

date.cycle('year', 5); // 2027-02-03
date.cycle('year', 5, {round: true}); // 2025-02-03

date.cycle('year', -5); // 2017-02-03
date.cycle('year', -5, {round: true}); // 2020-02-03

let date = new CalendarDate(2022, 2, 3);

date.cycle('year', 5); // 2027-02-03
date.cycle('year', 5, {round: true}); // 2025-02-03

date.cycle('year', -5); // 2017-02-03
date.cycle('year', -5, {round: true}); // 2020-02-03

let date =
  new CalendarDate(
    2022,
    2,
    3
  );

date.cycle('year', 5); // 2027-02-03
date.cycle('year', 5, {
  round: true
}); // 2025-02-03

date.cycle('year', -5); // 2017-02-03
date.cycle('year', -5, {
  round: true
}); // 2020-02-03

Note that if cycling a field causes another field to become invalid, the date is constrained. For example, adding one month to August 31st results in September 30th because September 31st does not exist.

Conversion#

To a string#

CalendarDate objects can be converted to an ISO 8601 formatted string using the toString method.

let date = new CalendarDate(2022, 2, 3);
date.toString(); // '2022-02-03'

let date = new CalendarDate(2022, 2, 3);
date.toString(); // '2022-02-03'

let date =
  new CalendarDate(
    2022,
    2,
    3
  );
date.toString(); // '2022-02-03'

To a native Date object#

A CalendarDate can be converted to a native JavaScript Date object using the toDate method. In general, the Date object should be avoided because it has many internationalization issues and other flaws. However, it is necessary to use some functionality like date formatting.

Because a Date represents an exact time, a time zone identifier is required to be passed to the toDate method. The time of the returned date will be set to midnight in that time zone. The getLocalTimeZone function can be used to retrieve the user's current time zone.

import {getLocalTimeZone} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);
date.toDate('America/Los_Angeles'); // Thu Feb 03 2022 00:00:00 GMT-0800 (Pacific Standard Time)
date.toDate(getLocalTimeZone()); // e.g. Thu Feb 03 2022 00:00:00 GMT-0500 (Eastern Standard Time)

import {getLocalTimeZone} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);
date.toDate('America/Los_Angeles'); // Thu Feb 03 2022 00:00:00 GMT-0800 (Pacific Standard Time)
date.toDate(getLocalTimeZone()); // e.g. Thu Feb 03 2022 00:00:00 GMT-0500 (Eastern Standard Time)

import {getLocalTimeZone} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    3
  );
date.toDate(
  'America/Los_Angeles'
); // Thu Feb 03 2022 00:00:00 GMT-0800 (Pacific Standard Time)
date.toDate(
  getLocalTimeZone()
); // e.g. Thu Feb 03 2022 00:00:00 GMT-0500 (Eastern Standard Time)

To a date with time#

A CalendarDate can be converted to a CalendarDateTime or ZonedDateTime by providing an optional Time object and/or time zone identifier.

A CalendarDateTime represents a date with a time, but not in any specific time zone. Use this type to represent times that occur at the same local time regardless of the time zone, such as the time of New Years Eve fireworks which always occur at midnight. Most times are better stored as a ZonedDateTime.

Use the toCalendarDateTime function to convert a CalendarDate to a CalendarDateTime. By default, the time will be set to midnight. You can also pass a Time object to set the time to a specific value.

import {toCalendarDateTime, Time} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);

toCalendarDateTime(date); // 2022-02-03T00:00:00
toCalendarDateTime(date, new Time(8, 30)); // 2022-02-03T08:30:00

import {
  Time,
  toCalendarDateTime
} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);

toCalendarDateTime(date); // 2022-02-03T00:00:00
toCalendarDateTime(date, new Time(8, 30)); // 2022-02-03T08:30:00

import {
  Time,
  toCalendarDateTime
} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    3
  );

toCalendarDateTime(date); // 2022-02-03T00:00:00
toCalendarDateTime(
  date,
  new Time(8, 30)
); // 2022-02-03T08:30:00

A ZonedDateTime represents a date with a time in a specific time zone. Use this type to represent an exact moment in time at a particular location on Earth.

Use the toZoned function to convert a CalendarDate to a ZonedDateTime. The time will be set to midnight in the given time zone. If you need to set a specific time, convert the CalendarDate to a CalendarDateTime first as described above, and pass the result to toZoned.

import {Time, toCalendarDateTime, toZoned} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);
toZoned(date, 'America/Los_Angeles'); // 2021-02-03T00:00-07:00[America/Los_Angeles]

let dateTime = toCalendarDateTime(date, new Time(8, 30));
toZoned(dateTime, 'America/Los_Angeles'); // 2021-02-03T08:30-07:00[America/Los_Angeles]

import {
  Time,
  toCalendarDateTime,
  toZoned
} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);
toZoned(date, 'America/Los_Angeles'); // 2021-02-03T00:00-07:00[America/Los_Angeles]

let dateTime = toCalendarDateTime(date, new Time(8, 30));
toZoned(dateTime, 'America/Los_Angeles'); // 2021-02-03T08:30-07:00[America/Los_Angeles]

import {
  Time,
  toCalendarDateTime,
  toZoned
} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    3
  );
toZoned(
  date,
  'America/Los_Angeles'
); // 2021-02-03T00:00-07:00[America/Los_Angeles]

let dateTime =
  toCalendarDateTime(
    date,
    new Time(8, 30)
  );
toZoned(
  dateTime,
  'America/Los_Angeles'
); // 2021-02-03T08:30-07:00[America/Los_Angeles]

Queries#

Comparison#

CalendarDate objects can be compared either for full or partial equality, or in order to determine which date is before or after another.

The compare method can be used to determine if a date is before or after another. It returns a number less than zero if the first date is before the second, zero if the values are equal, or a number greater than zero if the first date is after the second.

let a = new CalendarDate(2022, 2, 3);
let b = new CalendarDate(2022, 3, 4);

a.compare(b) < 0; // true
b.compare(a) > 0; // true

let a = new CalendarDate(2022, 2, 3);
let b = new CalendarDate(2022, 3, 4);

a.compare(b) < 0; // true
b.compare(a) > 0; // true

let a = new CalendarDate(
  2022,
  2,
  3
);
let b = new CalendarDate(
  2022,
  3,
  4
);

a.compare(b) < 0; // true
b.compare(a) > 0; // true

In addition, the following functions can be used to perform a partial comparison. These functions accept dates in different calendar systems, and the second date is converted to the calendar system of the first date before comparison.

isSameYear – Returns whether the given dates occur in the same year, using the calendar system of the first date.
isSameMonth – Returns whether the given dates occur in the same month, using the calendar system of the first date.
isSameDay – Returns whether the given dates occur on the same day, regardless of the time or calendar system.
isToday – Returns whether the date is today in the given time zone.

import {IslamicUmalquraCalendar, isSameMonth} from '@internationalized/date';

isSameMonth(new CalendarDate(2021, 4, 16), new CalendarDate(2021, 4, 30)); // true
isSameMonth(new CalendarDate(2021, 4, 16), new CalendarDate(2021, 8, 2)); // false
isSameMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(new IslamicUmalquraCalendar(), 1442, 9, 4)
); // true

import {
  IslamicUmalquraCalendar,
  isSameMonth
} from '@internationalized/date';

isSameMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(2021, 4, 30)
); // true
isSameMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(2021, 8, 2)
); // false
isSameMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(
    new IslamicUmalquraCalendar(),
    1442,
    9,
    4
  )
); // true

import {
  IslamicUmalquraCalendar,
  isSameMonth
} from '@internationalized/date';

isSameMonth(
  new CalendarDate(
    2021,
    4,
    16
  ),
  new CalendarDate(
    2021,
    4,
    30
  )
); // true
isSameMonth(
  new CalendarDate(
    2021,
    4,
    16
  ),
  new CalendarDate(
    2021,
    8,
    2
  )
); // false
isSameMonth(
  new CalendarDate(
    2021,
    4,
    16
  ),
  new CalendarDate(
    new IslamicUmalquraCalendar(),
    1442,
    9,
    4
  )
); // true

A similar set of functions is also available that does not convert between calendar systems and requires the calendars to be equal.

isEqualYear – Returns whether the given dates occur in the same year, and are of the same calendar system.
isEqualMonth – Returns whether the given dates occur in the same month, and are of the same calendar system.
isEqualDay – Returns whether the given dates occur on the same day, and are of the same calendar system.

import {isEqualMonth, IslamicUmalquraCalendar} from '@internationalized/date';

isEqualMonth(new CalendarDate(2021, 4, 16), new CalendarDate(2021, 4, 30)); // true
isEqualMonth(new CalendarDate(2021, 4, 16), new CalendarDate(2021, 8, 2)); // false
isEqualMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(new IslamicUmalquraCalendar(), 1442, 9, 4)
); // false

import {
  isEqualMonth,
  IslamicUmalquraCalendar
} from '@internationalized/date';

isEqualMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(2021, 4, 30)
); // true
isEqualMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(2021, 8, 2)
); // false
isEqualMonth(
  new CalendarDate(2021, 4, 16),
  new CalendarDate(
    new IslamicUmalquraCalendar(),
    1442,
    9,
    4
  )
); // false

import {
  isEqualMonth,
  IslamicUmalquraCalendar
} from '@internationalized/date';

isEqualMonth(
  new CalendarDate(
    2021,
    4,
    16
  ),
  new CalendarDate(
    2021,
    4,
    30
  )
); // true
isEqualMonth(
  new CalendarDate(
    2021,
    4,
    16
  ),
  new CalendarDate(
    2021,
    8,
    2
  )
); // false
isEqualMonth(
  new CalendarDate(
    2021,
    4,
    16
  ),
  new CalendarDate(
    new IslamicUmalquraCalendar(),
    1442,
    9,
    4
  )
); // false

Start and end dates#

The following functions can be used to find the start or end dates of a particular unit of time.

startOfYear – Returns the first day of the year for the given date.
endOfYear – Returns the last day of the year for the given date.
startOfMonth – Returns the first date of the month for the given date.
endOfMonth – Returns the last date of the month for the given date.
startOfWeek – Returns the first date of the week for the given date and locale.
endOfWeek – Returns the last date of the week for the given date and locale.

Note that startOfWeek and endOfWeek require a locale string to be provided. This is because the first day of the week changes depending on the locale. For example, in the United States, the first day of the week is on Sunday, but in France it is on Monday.

import {startOfYear, startOfMonth, startOfWeek} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);

startOfYear(date); // 2022-01-01
startOfMonth(date); // 2022-02-01
startOfWeek(date, 'en-US'); // 2022-01-30
startOfWeek(date, 'fr-FR'); // 2022-01-31

import {
  startOfMonth,
  startOfWeek,
  startOfYear
} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 3);

startOfYear(date); // 2022-01-01
startOfMonth(date); // 2022-02-01
startOfWeek(date, 'en-US'); // 2022-01-30
startOfWeek(date, 'fr-FR'); // 2022-01-31

import {
  startOfMonth,
  startOfWeek,
  startOfYear
} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    3
  );

startOfYear(date); // 2022-01-01
startOfMonth(date); // 2022-02-01
startOfWeek(
  date,
  'en-US'
); // 2022-01-30
startOfWeek(
  date,
  'fr-FR'
); // 2022-01-31

Day of week#

The getDayOfWeek function returns the day of the week for the given date and locale. Days are numbered from zero to six, where zero is the first day of the week in the given locale. For example, in the United States, the first day of the week is Sunday, but in France it is Monday.

import {getDayOfWeek} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 6); // a Sunday

getDayOfWeek(date, 'en-US'); // 0
getDayOfWeek(locale, 'fr-FR'); // 6

import {getDayOfWeek} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 6); // a Sunday

getDayOfWeek(date, 'en-US'); // 0
getDayOfWeek(locale, 'fr-FR'); // 6

import {getDayOfWeek} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    6
  ); // a Sunday

getDayOfWeek(
  date,
  'en-US'
); // 0
getDayOfWeek(
  locale,
  'fr-FR'
); // 6

Weekdays and weekends#

The isWeekday and isWeekend functions can be used to determine if a date is weekday or weekend respectively. This depends on the locale. For example, in the United States, weekends are Saturday and Sunday, but in Israel they are Friday and Saturday.

import {isWeekday, isWeekend} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 6); // a Sunday

isWeekday(date, 'en-US'); // false
isWeekday(date, 'he-IL'); // true

isWeekend(date, 'en-US'); // true
isWeekend(date, 'he-IL'); // false

import {
  isWeekday,
  isWeekend
} from '@internationalized/date';

let date = new CalendarDate(2022, 2, 6); // a Sunday

isWeekday(date, 'en-US'); // false
isWeekday(date, 'he-IL'); // true

isWeekend(date, 'en-US'); // true
isWeekend(date, 'he-IL'); // false

import {
  isWeekday,
  isWeekend
} from '@internationalized/date';

let date =
  new CalendarDate(
    2022,
    2,
    6
  ); // a Sunday

isWeekday(date, 'en-US'); // false
isWeekday(date, 'he-IL'); // true

isWeekend(date, 'en-US'); // true
isWeekend(date, 'he-IL'); // false

Weeks in month#

The getWeeksInMonth function returns the number of weeks in the given month. This depends on the number of days in the month, what day of the week the month starts on, and the given locale. For example, in the United States, the first day of the week is Sunday, but in France it is Monday.

import {getWeeksInMonth} from '@internationalized/date';

let date = new CalendarDate(2021, 1, 1);

getWeeksInMonth(date, 'en-US'); // 6
getWeeksInMonth(date, 'fr-FR'); // 5

import {getWeeksInMonth} from '@internationalized/date';

let date = new CalendarDate(2021, 1, 1);

getWeeksInMonth(date, 'en-US'); // 6
getWeeksInMonth(date, 'fr-FR'); // 5

import {getWeeksInMonth} from '@internationalized/date';

let date =
  new CalendarDate(
    2021,
    1,
    1
  );

getWeeksInMonth(
  date,
  'en-US'
); // 6
getWeeksInMonth(
  date,
  'fr-FR'
); // 5

Parses an ISO 8601 date string, with no time components.

parseDate(
  (value: string
)): CalendarDate

A CalendarDate represents a date without any time components in a specific calendar system.

Properties

Name	Type	Description
`calendar`	`Calendar`	The calendar system associated with this date, e.g. Gregorian.
`era`	`string`	The calendar era for this date, e.g. "BC" or "AD".
`year`	`number`	The year of this date within the era.
`month`	`number`	The month number within the year. Note that some calendar systems such as Hebrew may have a variable number of months per year. Therefore, month numbers may not always correspond to the same month names in different years.
`day`	`number`	The day number within the month.

Methods

Method	Description
`constructor( (...args: any[] )): void`
`copy(): CalendarDate`	Returns a copy of this date.
`add( (duration: DateDuration )): CalendarDate`	Returns a new `CalendarDate` with the given duration added to it.
`subtract( (duration: DateDuration )): CalendarDate`	Returns a new `CalendarDate` with the given duration subtracted from it.
`set( (fields: DateFields )): CalendarDate`	Returns a new `CalendarDate` with the given fields set to the provided values. Other fields will be constrained accordingly.
`cycle( field: DateField, amount: number, options?: CycleOptions ): CalendarDate`	Returns a new `CalendarDate` with the given field adjusted by a specified amount. When the resulting value reaches the limits of the field, it wraps around.
`toDate( (timeZone: string )): Date`	Converts the date to a native JavaScript Date object, with the time set to midnight in the given time zone.
`toString(): string`	Converts the date to an ISO 8601 formatted string.
`compare( (b: AnyCalendarDate )): number`	Compares this date with another. A negative result indicates that this date is before the given one, and a positive date indicates that it is after.

Returns today's date in the given time zone.

today(
  (timeZone: string
)): CalendarDate

Returns the time zone identifier for the current user.

getLocalTimeZone(): string

The Calendar interface represents a calendar system, including information about how days, months, years, and eras are organized, and methods to perform arithmetic on dates.

Properties

Name	Type	Description
`identifier`	`string`	A string identifier for the calendar, as defined by Unicode CLDR.

Methods

Method	Description
`fromJulianDay( (jd: number )): CalendarDate`	Creates a CalendarDate in this calendar from the given Julian day number.
`toJulianDay( (date: AnyCalendarDate )): number`	Converts a date in this calendar to a Julian day number.
`getDaysInMonth( (date: AnyCalendarDate )): number`	Returns the number of days in the month of the given date.
`getMonthsInYear( (date: AnyCalendarDate )): number`	Returns the number of months in the year of the given date.
`getYearsInEra( (date: AnyCalendarDate )): number`	Returns the number of years in the era of the given date.
`getEras(): string[]`	Returns a list of era identifiers for the calendar.
`getMinimumMonthInYear( (date: AnyCalendarDate )): number`	Returns the minimum month number of the given date's year. Normally, this is 1, but in some calendars such as the Japanese, eras may begin in the middle of a year.
`getMinimumDayInMonth( (date: AnyCalendarDate )): number`	Returns the minimum day number of the given date's month. Normally, this is 1, but in some calendars such as the Japanese, eras may begin in the middle of a month.

Name	Type	Description
`calendar`	`Calendar`
`era`	`string`
`year`	`number`
`month`	`number`
`day`	`number`

Method	Description
`copy():`

Converts a date from one calendar system to another.

toCalendar<T extends AnyCalendarDate>(
  (date: T,
  , calendar: Calendar
)): T

Represents an amount of time in calendar-specific units, for use when performing arithmetic.

Name	Type	Description
`years`	`number`	The number of years to add or subtract.
`months`	`number`	The number of months to add or subtract.
`weeks`	`number`	The number of weeks to add or subtract.
`days`	`number`	The number of days to add or subtract.

A CalendarDateTime represents a date and time without a time zone, in a specific calendar system.

Properties

Name	Type	Description
`calendar`	`Calendar`	The calendar system associated with this date, e.g. Gregorian.
`era`	`string`	The calendar era for this date, e.g. "BC" or "AD".
`year`	`number`	The year of this date within the era.
`month`	`number`	The month number within the year. Note that some calendar systems such as Hebrew may have a variable number of months per year. Therefore, month numbers may not always correspond to the same month names in different years.
`day`	`number`	The day number within the month.
`hour`	`number`	The hour in the day, numbered from 0 to 23.
`minute`	`number`	The minute in the hour.
`second`	`number`	The second in the minute.
`millisecond`	`number`	The millisecond in the second.

Methods

Method	Description
`constructor( (...args: any[] )): void`
`copy(): CalendarDateTime`	Returns a copy of this date.
`add( (duration: DateTimeDuration )): CalendarDateTime`	Returns a new `CalendarDateTime` with the given duration added to it.
`subtract( (duration: DateTimeDuration )): CalendarDateTime`	Returns a new `CalendarDateTime` with the given duration subtracted from it.
`set( (fields: DateFields & & TimeFields )): CalendarDateTime`	Returns a new `CalendarDateTime` with the given fields set to the provided values. Other fields will be constrained accordingly.
`cycle( field: DateField \| \| TimeField, amount: number, options?: CycleTimeOptions ): CalendarDateTime`	Returns a new `CalendarDateTime` with the given field adjusted by a specified amount. When the resulting value reaches the limits of the field, it wraps around.
`toDate( (timeZone: string, , disambiguation?: Disambiguation )): Date`	Converts the date to a native JavaScript Date object in the given time zone.
`toString(): string`	Converts the date to an ISO 8601 formatted string.
`compare( (b: CalendarDate \| CalendarDateTime \| ZonedDateTime )): number`	Compares this date with another. A negative result indicates that this date is before the given one, and a positive date indicates that it is after.

A ZonedDateTime represents a date and time in a specific time zone and calendar system.

Properties

Name	Type	Description
`calendar`	`Calendar`	The calendar system associated with this date, e.g. Gregorian.
`era`	`string`	The calendar era for this date, e.g. "BC" or "AD".
`year`	`number`	The year of this date within the era.
`month`	`number`	The month number within the year. Note that some calendar systems such as Hebrew may have a variable number of months per year. Therefore, month numbers may not always correspond to the same month names in different years.
`day`	`number`	The day number within the month.
`hour`	`number`	The hour in the day, numbered from 0 to 23.
`minute`	`number`	The minute in the hour.
`second`	`number`	The second in the minute.
`millisecond`	`number`	The millisecond in the second.
`timeZone`	`string`	The IANA time zone identifier that this date and time is represented in.
`offset`	`number`	The UTC offset for this time, in seconds.

Methods

Method	Description
`constructor( (...args: any[] )): void`
`copy(): ZonedDateTime`	Returns a copy of this date.
`add( (duration: DateTimeDuration )): void`	Returns a new `ZonedDateTime` with the given duration added to it.
`subtract( (duration: DateTimeDuration )): void`	Returns a new `ZonedDateTime` with the given duration subtracted from it.
`set( (fields: DateFields & & TimeFields, , disambiguation?: Disambiguation )): void`	Returns a new `ZonedDateTime` with the given fields set to the provided values. Other fields will be constrained accordingly.
`cycle( field: DateField \| \| TimeField, amount: number, options?: CycleTimeOptions ): void`	Returns a new `ZonedDateTime` with the given field adjusted by a specified amount. When the resulting value reaches the limits of the field, it wraps around.
`toDate(): void`	Converts the date to a native JavaScript Date object.
`toString(): void`	Converts the date to an ISO 8601 formatted string, including the UTC offset and time zone identifier.
`toAbsoluteString(): void`	Converts the date to an ISO 8601 formatted string in UTC.
`compare( (b: CalendarDate \| CalendarDateTime \| ZonedDateTime )): void`	Compares this date with another. A negative result indicates that this date is before the given one, and a positive date indicates that it is after.

Converts a date value to a CalendarDateTime. An optional Time value can be passed to set the time of the resulting value, otherwise it will default to midnight.

toCalendarDateTime(
  (date: CalendarDate
  | CalendarDateTime
  | ZonedDateTime,
  , time?: AnyTime
)): CalendarDateTime

Name	Type	Description
`hour`	`number`
`minute`	`number`
`second`	`number`
`millisecond`	`number`

Method	Description
`copy():`

A Time represents a clock time without any date components.

Properties

Name	Type	Description
`hour`	`number`	The hour, numbered from 0 to 23.
`minute`	`number`	The minute in the hour.
`second`	`number`	The second in the minute.
`millisecond`	`number`	The millisecond in the second.

Methods

Method	Description
`constructor( hour: number, minute: number, second: number, millisecond: number ): void`
`copy(): Time`	Returns a copy of this time.
`add( (duration: TimeDuration )): void`	Returns a new `Time` with the given duration added to it.
`subtract( (duration: TimeDuration )): void`	Returns a new `Time` with the given duration subtracted from it.
`set( (fields: TimeFields )): void`	Returns a new `Time` with the given fields set to the provided values. Other fields will be constrained accordingly.
`cycle( field: TimeField, amount: number, options?: CycleTimeOptions ): void`	Returns a new `Time` with the given field adjusted by a specified amount. When the resulting value reaches the limits of the field, it wraps around.
`toString(): void`	Converts the time to an ISO 8601 formatted string.
`compare( (b: AnyTime )): void`	Compares this time with another. A negative result indicates that this time is before the given one, and a positive time indicates that it is after.

Converts a date value to a ZonedDateTime in the provided time zone. The disambiguation option can be set to control how values that fall on daylight saving time changes are interpreted.

toZoned(
  date: CalendarDate
    | CalendarDateTime
    | ZonedDateTime,
  timeZone: string,
  disambiguation?: Disambiguation
): ZonedDateTime

'compatible'
  | 'earlier'
  | 'later'
  | 'reject'

Returns whether the given dates occur in the same year, using the calendar system of the first date.

isSameYear(
  (a: DateValue,
  , b: DateValue
)): boolean

CalendarDate
  | CalendarDateTime
  | ZonedDateTime

Returns whether the given dates occur in the same month, using the calendar system of the first date.

isSameMonth(
  (a: DateValue,
  , b: DateValue
)): boolean

Returns whether the given dates occur on the same day, regardless of the time or calendar system.

isSameDay(
  (a: DateValue,
  , b: DateValue
)): boolean

Returns whether the date is today in the given time zone.

isToday(
  (date: DateValue,
  , timeZone: string
)): boolean

Returns whether the given dates occur in the same year, and are of the same calendar system.

isEqualYear(
  (a: DateValue,
  , b: DateValue
)): boolean

Returns whether the given dates occur in the same month, and are of the same calendar system.

isEqualMonth(
  (a: DateValue,
  , b: DateValue
)): boolean

Returns whether the given dates occur on the same day, and are of the same calendar system.

isEqualDay(
  (a: DateValue,
  , b: DateValue
)): boolean

Returns the first day of the year for the given date.

startOfYear(
  (date: DateValue
)): DateValue

Returns the last day of the year for the given date.

endOfYear(
  (date: DateValue
)): DateValue

Returns the first date of the month for the given date.

startOfMonth(
  (date: DateValue
)): DateValue

Returns the last date of the month for the given date.

endOfMonth(
  (date: DateValue
)): DateValue

Returns the first date of the week for the given date and locale.

startOfWeek(
  (date: DateValue,
  , locale: string
)): DateValue

Returns the last date of the week for the given date and locale.

endOfWeek(
  (date: DateValue,
  , locale: string
)): DateValue

Returns the day of week for the given date and locale. Days are numbered from zero to six, where zero is the first day of the week in the given locale. For example, in the United States, the first day of the week is Sunday, but in France it is Monday.

getDayOfWeek(
  (date: DateValue,
  , locale: string
)): number

Returns whether the given date is on a weekday in the given locale.

isWeekday(
  (date: DateValue,
  , locale: string
)): boolean

Returns whether the given date is on a weekend in the given locale.

isWeekend(
  (date: DateValue,
  , locale: string
)): boolean

Returns the number of weeks in the given month and locale.

getWeeksInMonth(
  (date: DateValue,
  , locale: string
)): number