date-utils

This is a collection of utility methods for the Date object.

Install

Using npm:

npm i @pj1401/date-utils

Usage

Import:

import { DateUtil } from "@pj1401/date-utils";

const dateUtil = new DateUtil()

Methods:

• countDays
• getWeekNumber
• getOrdinalDate
• getDaysBetween
• getDatesBetween
• getQuarter
• isBetween
• startOfWeek
• endOfWeek
• getDaysUntilWeekend
• countWorkingDays
• addDays
• removeDays

countDays

countDays(date: Date): number

Returns the number of days until a date. If the date is in the past, the number of days passed is returned (negative).

const nextWeek = new Date()
nextWeek.setDate(nextWeek.getDate() + 7)

dateUtil.countDays(nextWeek) // returns 7

dateUtil.countDays(new Date('2025-09-30')) // returns a negative number

getWeekNumber

getWeekNumber(date: Date): number

Returns the number of the week that the date is in.

dateUtil.getWeekNumber(new Date('2025-09-17')) // returns 38

getOrdinalDate

getOrdinalDate(date: Date): number

Returns the number representing the day of the year.

dateUtil.getOrdinalDate(new Date('2025-09-30')) // returns 273

getDaysBetween

getDaysBetween(date1: Date, date2: Date): number

Returns the number of days between two dates.

dateUtil.getDaysBetween(new Date('2025-09-15'), new Date('2025-09-22')) // returns 7

getDatesBetween

getDatesBetween(startDate: Date, endDate: Date): Date[]

Get an array of dates between two dates, inclusive.

dateUtil.getDatesBetween(new Date('2025-10-25'), new Date('2025-11-02'))

getQuarter

getQuarter(date: Date): number

Returns the quarter of the year the date is in.

dateUtil.getQuarter(new Date('2025-10-01')) // returns 4

isBetween

isBetween(date: Date, startDate: Date, endDate: Date): boolean

Check if a date is in the interval [startDate, endDate].

dateUtil.isBetween(new Date('2025-09-30'), new Date('2025-09-29'), new Date('2025-10-01')) // true

startOfWeek

startOfWeek(date: Date): Date

Returns the start (Monday) of the week the date is in.

dateUtil.startOfWeek(new Date('2025-09-30')) // returns a Date object set to 2025-09-29

endOfWeek

endOfWeek(date: Date): Date

Returns the end (Sunday) of the week the date is in.

dateUtil.endOfWeek(new Date('2025-09-30')) // returns a Date object set to 2025-10-05

getDaysUntilWeekend

getDaysUntilWeekend(date: Date): number

Get the number of days until the weekend (Saturday). If the date argument is a Sunday, it counts the days until the next weekend. If no argument is passed the current date will be used.

dateUtil.getDaysUntilWeekend(new Date('2025-11-05')) // returns 3

countWorkingDays

countWorkingDays(startDate: Date, endDate: Date): number

Get the number of working days between two dates.

dateUtil.countWorkingDays(new Date('2025-10-20'), new Date('2025-11-01')) // returns 10

addDays

addDays(date: Date, numberOfDays: number): Date

Add days to the date. The returned date is a different instance from the date argument.

dateUtil.addDays(new Date('2025-01-30'), 5) // returns a Date object set to 2025-02-04

removeDays

removeDays(date: Date, numberOfDays: number): Date

Remove days from the date. The returned date is a different instance from the date argument.

dateUtil.addDays(new Date('2025-01-03'), 10) // returns a Date object set to 2024-12-24

Testing

See Testing instructions