FrostDateTime

FrostDateTime is a free, open-source immutable date manipulation library for JavaScript.

It is a lightweight (~7kb gzipped) and modern library, and features support for ICU formats, time zones and locales.

Table Of Contents

• Installation
• Date Creation
• Date Formatting
• Date Attributes
• Week Attributes
• Time Attributes
• Timestamps
• Time Zones
• Locales
• Manipulation
• Comparisons
• Utility Methods
• Static Methods

Installation

In Browser

<script type="text/javascript" src="/path/to/frost-datetime.min.js"></script>

Using NPM

npm i @fr0st/datetime

In Node.js:

import DateTime from '@fr0st/datetime';

Date Creation

• dateString is a string representing the date, and will default to the current timestamp.
• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to the system locale.

const dateTime = new DateTime(dateString, options);

From Array

• dateArray is an array containing the year, month, date, hours, minutes, seconds and milliseconds.
• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to the system locale.

const dateTime = DateTime.fromArray(dateArray, options);

The month and date in the dateArray will default to 1 if not set. The hours, minutes, seconds and milliseconds will default to 0.

From Date

• dateObj is a native JS Date object.
• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to the system locale.

const dateTime = DateTime.fromDate(dateObj, options);

From Format

If you wish to parse a date string and you know the exact format, you can use the fromFormat static method.

• formatString is a string containing the format you wish to use for parsing.
• dateString is a string representing the date you are parsing.
• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to the system locale.

The formatString supports a subset of the ICU specification described in Formats.

The isValid property on the created DateTime object can be used to determine whether a formatted string was a valid date.

const dateTime = DateTime.fromFormat(formatString, dateString, options);

From ISO String

• dateString is a string representing the date you are parsing.
• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to English.

The dateString must be in yyyy-MM-dd'T'HH:mm:ss.SSSxxx" format and in English.

If the timeZone option is also passed, the created DateTime will be converted to the new timeZone.

The isValid property on the created DateTime object can be used to determine whether a formatted string was a valid date.

const dateTime = DateTime.fromISOString(dateString, options);

From Timestamp

• timestamp is the number of seconds since the UNIX epoch.
• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to the system locale.

const dateTime = DateTime.fromTimestamp(timestamp, options);

Now

• options is an object containing options for creating the new date.
  • timeZone is a string representing the time zone of the date, and will default to the system time zone.
  • locale is a string representing the locale of the date, and will default to the system locale.

const dateTime = DateTime.now(options);

Date Formatting

Format

Once you have created a DateTime object, you can get a string representation using a specific format with the format method.

• formatString is a string containing the format you wish to output using.

The formatString supports a subset of the ICU specification described in Formats.

const dateString = dateTime.format(formatString);

To String

Format the current date using "eee MMM dd yyyy HH:mm:ss xx (VV)".

const string = dateTime.toString();

To Date String

Format the current date using "eee MMM dd yyyy".

const dateString = dateTime.toDateString();

To ISO String

Format the current date using "yyyy-MM-dd'T'HH:mm:ss.SSSxxx" (in English and UTC time zone).

const isoString = dateTime.toISOString();

To Time String

Format the current date using "HH:mm:ss xx (VV)".

const timeString = dateTime.toTimeString();

To UTC String

Format the current date using "eee MMM dd yyyy HH:mm:ss xx (VV)" (in UTC time zone).

const utcString = dateTime.toUTCString();

Date Attributes

Get Date

Get the date in current time zone.

const date = dateTime.getDate();

Get Day

Get the day of the week in current time zone.

The day returned will be between 0 (Sunday) and 6 (Saturday).

const day = dateTime.getDay();

Get Day Of Year

Get the day of the year in current time zone.

The dayOfYear returned will be between 0 and 365.

const dayOfYear = dateTime.getDayOfYear();

Get Month

Get the month in current time zone.

The month returned will be between 1 (January) and 12 (December).

const month = dateTime.getMonth();

Get Quarter

Get the quarter of the year in current time zone.

The quarter returned will be between 1 and 4.

const quarter = dateTime.getQuarter();

Get Year

Get the year in current time zone.

const year = dateTime.getYear();

Set Date

Set the date in current time zone.

• date is a number representing the date.

const newDateTime = dateTime.setDate(date);

Set Day

Set the day of the week in current time zone.

• day is a number representing the day of the week (between 0 and 6).

const newDateTime = dateTime.setDay(day);

Set Day Of Year

Set the day of the year in current time zone.

• dayOfYear is a number representing the day of the year (between 0 and 365).

const newDateTime = dateTime.setDayOfYear(dayOfYear);

Set Month

Set the month in current time zone.

• month is a number representing the month (between 1 and 12).
• date is a number representing the date, and will default to the current value.

If the date argument is omitted, and the new month contains less days than the current date, the date will be set to the last day of the new month.

To disable date clamping, use the method DateTime.setDateClamping() using false as the argument.

const newDateTime = dateTime.setMonth(month, date);

Set Quarter

Set the quarter of the year in current time zone.

• quarter is a number representing the quarter between 1 and 4.

const newDateTime = dateTime.setQuarter(quarter);

Set Year

Set the year in current time zone.

• year is a number representing the year.
• month is a number representing the month (between 1 and 12), and will default to the current value.
• date is a number representing the date, and will default to the current value.

If the date argument is omitted, and the new month contains less days than the current date, the date will be set to the last day of the new month.

To disable date clamping, use the method DateTime.setDateClamping() using false as the argument.

const newDateTime = dateTime.setYear(year, month, date);

Week Attributes

Get Week

Get the week of the year in current time zone.

The week returned will be between 1 and 53 (week starting on Monday).

const week = dateTime.getWeek();

Get Week Day

Get the local day of the week in current time zone.

The weekDay returned will be between 1 and 7.

const weekDay = dateTime.getWeekDay();

Get Week Day In Month

Get the day of the week in the month, in current time zone.

The weekDayInMonth returned will be between 1 and 5.

const weekDayInMonth = dateTime.getWeekDayInMonth();

Get Week Of Month

Get the week of the month in current time zone.

The weekOfMonth returned will be between 1 and 5.

const weekOfMonth = dateTime.getWeekOfMonth();

Get Week Year

Get the week year in current time zone.

This method is identical to getYear() except in cases where the week belongs to the previous or next year, then that value will be used instead.

const weekYear = dateTime.getWeekYear();

Set Week

Set the week in current time zone.

• week is a number representing the week.
• weekDay is a number representing the day (between 1 and 7), and will default to the current value.

const newDateTime = dateTime.setWeek(week, weekDay);

Set Week Day

Set the local day of the week in current time zone.

• weekDay is a number representing the week day (between 1 and 7).

const newDateTime = dateTime.setWeekDay(weekDay);

Set Week Day In Month

Set the day of the week in the month, in current time zone.

• weekDayInMonth is a number representing the day of the week in month (between 1 and 5).

const newDateTime = dateTime.setWeekDayInMonth(weekDayInMonth);

Set Week Of Month

Set the week of the month in current time zone.

• weekOfMonth is a number representing the week of the month (between 1 and 5).

const newDateTime = dateTime.setWeekOfMonth(weekOfMonth);

Set Week Year

Set the week year in current time zone.

• weekYear is a number representing the year.
• week is a number representing the week, and will default to the current value.
• weekDay is a number representing the day (between 1 and 7), and will default to the current value.

const newDateTime = dateTime.setWeekYear(weekYear, week, weekDay);

Time Attributes

Get Hours

Get the hours of the day in current time zone.

The hours returned will be between 0 and 23.

const hours = dateTime.getHours();

Get Milliseconds

Get the milliseconds of the second in current time zone.

The milliseconds returned will be between 0 and 999.

const milliseconds = dateTime.getMilliseconds();

Get Minutes

Get the minutes of the hour in current time zone.

The minutes returned will be between 0 and 59.

const minutes = dateTime.getMinutes();

Get Seconds

Get the seconds of the minute in current time zone.

The seconds returned will be between 0 and 59.

const seconds = dateTime.getSeconds();

Set Hours

Set the hours of the day in current time zone.

• hours is a number representing the hours of the day (between 0 and 23).
• minutes is a number representing the minutes of the hour (between 0 and 59), and will default to the current value.
• seconds is a number representing the seconds of the minute (between 0 and 59), and will default to the current value.
• milliseconds is a number representing the milliseconds of the second (between 0 and 999), and will default to the current value.

const newDateTime = dateTime.setHours(hours, minutes, seconds, milliseconds);

Set Milliseconds

Set the milliseconds of the second in current time zone.

• milliseconds is a number representing the milliseconds of the second (between 0 and 999).

const newDateTime = dateTime.setMilliseconds(milliseconds);

Set Minutes

Set the minutes of the hour in current time zone.

• minutes is a number representing the minutes of the hour (between 0 and 59).
• seconds is a number representing the seconds of the minute (between 0 and 59), and will default to the current value.
• milliseconds is a number representing the milliseconds of the second (between 0 and 999), and will default to the current value.

const newDateTime = dateTime.setMinutes(minutes, seconds, milliseconds);

Set Seconds

Set the seconds of the minute in current time zone.

• seconds is a number representing the seconds of the minute (between 0 and 59).
• milliseconds is a number representing the milliseconds of the second (between 0 and 999), and will default to the current value.

const newDateTime = dateTime.setSeconds(seconds, milliseconds);

Timestamps

Get Milliseconds

Get the number of milliseconds since the UNIX epoch.

const time = dateTime.getTime();

Get Seconds

Get the number of seconds since the UNIX epoch.

const timestamp = dateTime.getTimestamp();

Set Milliseconds

Set the number of milliseconds since the UNIX epoch.

const newDateTime = dateTime.setTime(time);

Set Seconds

Set the number of seconds since the UNIX epoch.

const newDateTime = dateTime.setTimestamp(timestamp);

Time Zones

Get Time Zone

Get the name of the current time zone.

const timeZone = dateTime.getTimeZone();

Get Time Zone Offset

Get the UTC offset (in minutes) of the current time zone.

const offset = dateTime.getTimeZoneOffset();

Set Time Zone

Set the current time zone.

• timeZone is the name of the new time zone, which can be either "UTC", a supported value from the IANA timeZone database or an offset string.

const newDateTime = dateTime.setTimeZone(timeZone);

Set Time Zone Offset

Set the UTC offset (in minutes).

• offset is the UTC offset (in minutes).

const newDateTime = dateTime.setTimeZoneOffset(offset);

Locales

Get Locale

Get the name of the current locale.

const locale = dateTime.getLocale();

Set Locale

Set the current locale.

• locale is the name of the new locale.

const newDateTime = dateTime.setLocale(locale);

Manipulation

Add Day

Add a day to the current date.

const newDateTime = dateTime.addDay();

Add Days

Add days to the current date.

• amount is a number representing the amount of days to add.

const newDateTime = dateTime.addDay(amount);

Add Hour

Add a hour to the current date.

const newDateTime = dateTime.addHour();

Add Hours

Add hours to the current date.

• amount is a number representing the amount of hours to add.

const newDateTime = dateTime.addHours(amount);

Add Minute

Add a minute to the current date.

const newDateTime = dateTime.addMinute();

Add Minutes

Add minutes to the current date.

• amount is a number representing the amount of minutes to add.

const newDateTime = dateTime.addMinutes(amount);

Add Month

Add a month to the current date.

const newDateTime = dateTime.addMonth();

Add Months

Add months to the current date.

• amount is a number representing the amount of months to add.

const newDateTime = dateTime.addMonths(amount);

Add Second

Add a second to the current date.

const newDateTime = dateTime.addSecond();

Add Seconds

Add seconds to the current date.

• amount is a number representing the amount of seconds to add.

const newDateTime = dateTime.addSeconds(amount);

Add Week

Add a week to the current date.

const newDateTime = dateTime.addWeek();

Add Weeks

Add weeks to the current date.

• amount is a number representing the amount of weeks to add.

const newDateTime = dateTime.addWeeks(amount);

Add Year

Add a year to the current date.

const newDateTime = dateTime.addYear();

Add Years

Add years to the current date.

• amount is a number representing the amount of years to add.

const newDateTime = dateTime.addYears(amount);

End Of Day

Set the date to the end of the day in current time zone.

const newDateTime = dateTime.endOfDay();

End Of Hour

Set the date to the end of the hour in current time zone.

const newDateTime = dateTime.endOfHour();

End Of Minute

Set the date to the end of the minute in current time zone.

const newDateTime = dateTime.endOfMinute();

End Of Month

Set the date to the end of the month in current time zone.

const newDateTime = dateTime.endOfMonth();

End Of Quarter

Set the date to the end of the quarter in current time zone.

const newDateTime = dateTime.endOfQuarter();

End Of Second

Set the date to the end of the second in current time zone.

const newDateTime = dateTime.endOfSecond();

End Of Week

Set the date to the end of the week in current time zone.

const newDateTime = dateTime.endOfWeek();

End Of Year

Set the date to the end of the year in current time zone.

const newDateTime = dateTime.endOfYear();

Start Of Day

Set the date to the start of the day in current time zone.

const newDateTime = dateTime.startOfDay();

Start Of Hour

Set the date to the start of the hour in current time zone.

const newDateTime = dateTime.startOfHour();

Start Of Minute

Set the date to the start of the minute in current time zone.

const newDateTime = dateTime.startOfMinute();

Start Of Month

Set the date to the start of the month in current time zone.

const newDateTime = dateTime.startOfMonth();

Start Of Quarter

Set the date to the start of the quarter in current time zone.

const newDateTime = dateTime.startOfQuarter();

Start Of Second

Set the date to the start of the second in current time zone.

const newDateTime = dateTime.startOfSecond();

Start Of Week

Set the date to the start of the week in current time zone.

const newDateTime = dateTime.startOfWeek();

Start Of Year

Set the date to the start of the year in current time zone.

const newDateTime = dateTime.startOfYear();

Subtract Day

Subtract a day to the current date.

const newDateTime = dateTime.subtractDay();

Subtract Days

Subtract days to the current date.

• amount is a number representing the amount of days to subtract.

const newDateTime = dateTime.subtractDay(amount);

Subtract Hour

Subtract a hour to the current date.

const newDateTime = dateTime.subtractHour();

Subtract Hours

Subtract hours to the current date.

• amount is a number representing the amount of hours to subtract.

const newDateTime = dateTime.subtractHours(amount);

Subtract Minute

Subtract a minute to the current date.

const newDateTime = dateTime.subtractMinute();

Subtract Minutes

Subtract minutes to the current date.

• amount is a number representing the amount of minutes to subtract.

const newDateTime = dateTime.subtractMinutes(amount);

Subtract Month

Subtract a month to the current date.

const newDateTime = dateTime.subtractMonth();

Subtract Months

Subtract months to the current date.

• amount is a number representing the amount of months to subtract.

const newDateTime = dateTime.subtractMonths(amount);

Subtract Second

Subtract a second to the current date.

const newDateTime = dateTime.subtractSecond();

Subtract Seconds

Subtract seconds to the current date.

• amount is a number representing the amount of seconds to subtract.

const newDateTime = dateTime.subtractSeconds(amount);

Subtract Week

Subtract a week to the current date.

const newDateTime = dateTime.subtractWeek();

Subtract Weeks

Subtract weeks to the current date.

• amount is a number representing the amount of weeks to subtract.

const newDateTime = dateTime.subtractWeeks(amount);

Subtract Year

Subtract a year to the current date.

const newDateTime = dateTime.subtractYear();

Subtract Years

Subtract years to the current date.

• amount is a number representing the amount of years to subtract.

const newDateTime = dateTime.subtractYears(amount);

Comparisons

Difference

Get the difference between two dates in milliseconds.

• other is the DateTime object to compare to.

const diff = dateTime.diff(other);

Difference In Days

Get the difference between two dates in days.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInDays(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Difference In Hours

Get the difference between two dates in hours.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInHours(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Difference In Minutes

Get the difference between two dates in minutes.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInMinutes(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Difference In Months

Get the difference between two dates in months.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInMonths(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Difference In Seconds

Get the difference between two dates in seconds.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInSeconds(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Difference In Weeks

Get the difference between two dates in weeks.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInWeeks(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Difference In Years

Get the difference between two dates in years.

• other is the DateTime object to compare to.
• options is an object containing options for how to compare the dates.
  • relative is a boolean indicating whether to return the relative difference, and will default to true.

const diff = dateTime.diffInYears(other, options);

If relative is true (default) the value returned will be the relative difference, ignoring higher precision properties.

Human Difference

Get the relative difference between two Dates in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiff(other);

The most significant non-zero value is determined where the unit of time has a non-relative difference, or the next relative difference value is greater than or equal to the unit of time.

DateTime.fromFormat('yyyy-MM-dd', '2019-01-01').humanDiff(DateTime.fromFormat('yyyy-MM-dd', '2018-12-31')); // "tomorrow"
DateTime.fromFormat('yyyy-MM-dd', '2019-02-27').humanDiff(DateTime.fromFormat('yyyy-MM-dd', '2019-01-31')); // "in 27 days"
DateTime.fromFormat('yyyy-MM-dd', '2019-02-28').humanDiff(DateTime.fromFormat('yyyy-MM-dd', '2019-01-31')); // "next month"
DateTime.fromFormat('yyyy-MM-dd', '2019-01-01').humanDiff(DateTime.fromFormat('yyyy-MM-dd', '2018-06-01')); // "in 6 months"
DateTime.fromFormat('yyyy-MM-dd', '2019-01-01').humanDiff(DateTime.fromFormat('yyyy-MM-dd', '2018-01-31')); // "next year"
DateTime.fromFormat('yyyy-MM-dd', '2019-01-01').humanDiff(DateTime.fromFormat('yyyy-MM-dd', '2017-12-31')); // "in 2 years"

Human Difference In Days

Get the relative difference between two Dates in days in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInDays(other);

Human Difference In Hours

Get the relative difference between two Dates in hours in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInHours(other);

Human Difference In Minutes

Get the relative difference between two Dates in minutes in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInMinutes(other);

Human Difference In Months

Get the relative difference between two Dates in months in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInMonths(other);

Human Difference In Seconds

Get the relative difference between two Dates in seconds in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInSeconds(other);

Human Difference In Weeks

Get the relative difference between two Dates in weeks in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInWeeks(other);

Human Difference In Years

Get the relative difference between two Dates in years in a human readable format using the current locale.

• other is the DateTime object to compare to.

const humanDiff = dateTime.humanDiffInYears(other);

Is After?

Return true if the DateTime is after another date.

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfter(other);

Is After Day?

Return true if the DateTime is after another date (comparing by day).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterDay(other);

Is After Hour?

Return true if the DateTime is after another date (comparing by hour).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterHour(other);

Is After Minute?

Return true if the DateTime is after another date (comparing by minute).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterMinute(other);

Is After Month?

Return true if the DateTime is after another date (comparing by month).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterMonth(other);

Is After Second?

Return true if the DateTime is after another date (comparing by second).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterSecond(other);

Is After Week?

Return true if the DateTime is after another date (comparing by week).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterWeek(other);

Is After Year?

Return true if the DateTime is after another date (comparing by year).

• other is the DateTime object to compare to.

const isAfter = dateTime.isAfterYear(other);

Is Before?

Return true if the DateTime is before another date.

• other is the DateTime object to compare to.

const isBefore = dateTime.isBefore(other);

Is Before Day?

Return true if the DateTime is before another date (comparing by day).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeDay(other);

Is Before Hour?

Return true if the DateTime is before another date (comparing by hour).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeHour(other);

Is Before Minute?

Return true if the DateTime is before another date (comparing by minute).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeMinute(other);

Is Before Month?

Return true if the DateTime is before another date (comparing by month).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeMonth(other);

Is Before Second?

Return true if the DateTime is before another date (comparing by second).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeSecond(other);

Is Before Week?

Return true if the DateTime is before another date (comparing by week).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeWeek(other);

Is Before Year?

Return true if the DateTime is before another date (comparing by year).

• other is the DateTime object to compare to.

const isBefore = dateTime.isBeforeYear(other);

Is Between?

Return true if the DateTime is between two other dates.

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetween(start, end);

Is Between Day?

Return true if the DateTime is between two other dates (comparing by day).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenDay(start, end);

Is Between Hour?

Return true if the DateTime is between two other dates (comparing by hour).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenHour(start, end);

Is Between Minute?

Return true if the DateTime is between two other dates (comparing by minute).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenMinute(start, end);

Is Between Month?

Return true if the DateTime is between two other dates (comparing by month).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenMonth(start, end);

Is Between Second?

Return true if the DateTime is between two other dates (comparing by second).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenSecond(start, end);

Is Between Week?

Return true if the DateTime is between two other dates (comparing by week).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenWeek(start, end);

Is Between Year?

Return true if the DateTime is between two other dates (comparing by year).

• start is the starting DateTime object to compare to.
• end is the ending DateTime object to compare to.

const isBetween = dateTime.isBetweenYear(start, end);

Is Same?

Return true if the DateTime is the same as another date.

• other is the DateTime object to compare to.

const isSame = dateTime.isSame(other);

Is Same Day?

Return true if the DateTime is the same as another date (comparing by day).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameDay(other);

Is Same Hour?

Return true if the DateTime is the same as another date (comparing by hour).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameHour(other);

Is Same Minute?

Return true if the DateTime is the same as another date (comparing by minute).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameMinute(other);

Is Same Month?

Return true if the DateTime is the same as another date (comparing by month).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameMonth(other);

Is Same Second?

Return true if the DateTime is the same as another date (comparing by second).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameSecond(other);

Is Same Week?

Return true if the DateTime is the same as another date (comparing by week).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameWeek(other);

Is Same Year?

Return true if the DateTime is the same as another date (comparing by year).

• other is the DateTime object to compare to.

const isSame = dateTime.isSameYear(other);

Is Same Or After?

Return true if the DateTime is the same as or after another date.

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfter(other);

Is Same Or After Day?

Return true if the DateTime is the same as or after another date (comparing by day).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterDay(other);

Is Same Or After Hour?

Return true if the DateTime is the same as or after another date (comparing by hour).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterHour(other);

Is Same Or After Minute?

Return true if the DateTime is the same as or after another date (comparing by minute).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterMinute(other);

Is Same Or After Month?

Return true if the DateTime is the same as or after another date (comparing by month).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterMonth(other);

Is Same Or After Second?

Return true if the DateTime is the same as or after another date (comparing by second).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterSecond(other);

Is Same Or After Week?

Return true if the DateTime is the same as or after another date (comparing by week).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterWeek(other);

Is Same Or After Year?

Return true if the DateTime is the same as or after another date (comparing by year).

• other is the DateTime object to compare to.

const isSameOrAfter = dateTime.isSameOrAfterYear(other);

Is Same Or Before?

Return true if the DateTime is the same as or before another date.

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBefore(other);

Is Same Or Before Day?

Return true if the DateTime is the same as or before another date (comparing by day).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeDay(other);

Is Same Or Before Hour?

Return true if the DateTime is the same as or before another date (comparing by hour).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeHour(other);

Is Same Or Before Minute?

Return true if the DateTime is the same as or before another date (comparing by minute).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeMinute(other);

Is Same Or Before Month?

Return true if the DateTime is the same as or before another date (comparing by month).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeMonth(other);

Is Same Or Before Second?

Return true if the DateTime is the same as or before another date (comparing by second).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeSecond(other);

Is Same Or Before Week?

Return true if the DateTime is the same as or before another date (comparing by week).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeWeek(other);

Is Same Or Before Year?

Return true if the DateTime is the same as or before another date (comparing by year).

• other is the DateTime object to compare to.

const isSameOrBefore = dateTime.isSameOrBeforeYear(other);

Utility Methods

Day Name

Get the name of the day of the week in current time zone and locale.

• type can be either "long", "short" or "narrow", and will default to "long" if it is not set.

const dayName = dateTime.dayName(type);

Day Period

Get the day period in current time zone and locale.

• type can be either "long" or "short", and will default to "long" if it is not set.

const dayPeriod = dateTime.dayPeriod(type);

Days In Month

Get the number of days in the current month.

const daysInMonth = dateTime.daysInMonth();

Days In Year

Get the number of days in the current year.

const daysInYear = dateTime.daysInYear();

Era

Get the era in current time zone and locale.

• type can be either "long", "short" or "narrow", and will default to "long" if it is not set.

const era = dateTime.era(type);

Is DST?

Return true if the DateTime is in daylight savings.

const isDST = dateTime.isDST();

Is Leap Year?

Return true if the year is a leap year.

const isLeapYear = dateTime.isLeapYear();

Month Name

Get the name of the month in current time zone and locale.

• type can be either "long", "short" or "narrow", and will default to "long" if it is not set.

const monthName = dateTime.monthName(type);

Time Zone Name

Get the name of the current time zone and locale.

• type can be either "long" or "short", and will default to "long" if it is not set.

const timeZoneName = dateTime.timeZoneName(type);

Weeks In Year

Get the number of weeks in the current year.

const weeksInYear = dateTime.weeksInYear();

Static Methods

Day Of Year

Get the day of the year for a year, month and date.

• year is a number representing the year.
• month is a number representing the month (between 1 and 12).
• date is a number representing the date.

const dayOfYear = DateTime.dayOfYear(year, month, date);

Days In Month

Get the number of days in a month, from a year and month.

• year is a number representing the year.
• month is a number representing the month (between 1 and 12).

const daysInMonth = DateTime.daysInMonth(year, month);

Days In Year

Get the number of days in a year.

• year is a number representing the year.

const daysInYear = DateTime.daysInYear(year);

Get Default Locale

Get the default locale.

const locale = DateTime.getDefaultLocale();

Get Default Time Zone

Get the default time zone.

const timeZone = DateTime.getDefaultTimeZone();

Is Leap Year?

Return true if the year is a leap year.

• year is a number representing the year.

const isLeapYear = DateTime.isLeapYear(year);

Set Date Clamping

Set whether dates will be clamped when changing months.

• clampDates is a boolean indicating whether to clamp dates.

DateTime.setDateClamping(clampDates);

Set Default Locale

Set the default locale.

• locale is the name of the locale.

DateTime.setDefaultLocale(locale);

Set Default Time Zone

Set the default time zone.

• timeZone is the name of the time zone, which can be either "UTC", a supported value from the IANA timeZone database or an offset string.

DateTime.setDefaultTimeZone(timeZone);