Constants

The library exports several constants for month names, weekday names, Nepali numerals, and the complete date mapping table.

Import

import {
  // Month names
  MONTH_EN,
  MONTH_NP,
  MONTH_SHORT_EN,
  MONTH_SHORT_NP,

  // Weekday names
  WEEK_EN,
  WEEK_NP,
  WEEK_SHORT_EN,
  WEEK_SHORT_NP,

  // Nepali numerals
  NUMBER_NP,

  // Date map
  NEPALI_DATE_MAP,
} from "nepali-date-library";

---

Month Names

MONTH_EN

Full English month names.

const MONTH_EN: string[] = [
  "Baisakh",
  "Jestha",
  "Asar",
  "Shrawan",
  "Bhadra",
  "Aswin",
  "Kartik",
  "Mangsir",
  "Poush",
  "Magh",
  "Falgun",
  "Chaitra",
];

Example:

console.log(MONTH_EN[0]); // 'Baisakh'
console.log(MONTH_EN[9]); // 'Magh'
console.log(MONTH_EN[11]); // 'Chaitra'

---

MONTH_SHORT_EN

Short English month names (3 characters).

const MONTH_SHORT_EN: string[] = [
  "Bai",
  "Jes",
  "Asa",
  "Shr",
  "Bhd",
  "Asw",
  "Kar",
  "Man",
  "Pou",
  "Mag",
  "Fal",
  "Cha",
];

---

MONTH_NP

Full Nepali month names in Devanagari script.

const MONTH_NP: string[] = [
  "बैशाख",
  "जेठ",
  "असार",
  "श्रावण",
  "भाद्र",
  "आश्विन",
  "कार्तिक",
  "मंसिर",
  "पौष",
  "माघ",
  "फाल्गुण",
  "चैत्र",
];

Example:

console.log(MONTH_NP[0]); // 'बैशाख'
console.log(MONTH_NP[9]); // 'माघ'

---

MONTH_SHORT_NP

Short Nepali month names.

const MONTH_SHORT_NP: string[] = [
  "बै",
  "जे",
  "अ",
  "श्रा",
  "भा",
  "आ",
  "का",
  "मं",
  "पौ",
  "मा",
  "फा",
  "चै",
];

---

Month Reference Table

Index	MONTH_EN	MONTH_SHORT_EN	MONTH_NP	MONTH_SHORT_NP
0	Baisakh	Bai	बैशाख	बै
1	Jestha	Jes	जेठ	जे
2	Asar	Asa	असार	अ
3	Shrawan	Shr	श्रावण	श्रा
4	Bhadra	Bhd	भाद्र	भा
5	Aswin	Asw	आश्विन	आ
6	Kartik	Kar	कार्तिक	का
7	Mangsir	Man	मंसिर	मं
8	Poush	Pou	पौष	पौ
9	Magh	Mag	माघ	मा
10	Falgun	Fal	फाल्गुण	फा
11	Chaitra	Cha	चैत्र	चै

---

Weekday Names

WEEK_EN

Full English day names.

const WEEK_EN: string[] = [
  "Sunday",
  "Monday",
  "Tuesday",
  "Wednesday",
  "Thursday",
  "Friday",
  "Saturday",
];

Example:

const dayIndex = new NepaliDate().getDay();
console.log(WEEK_EN[dayIndex]); // 'Wednesday'

---

WEEK_SHORT_EN

Short English day names (3 characters).

const WEEK_SHORT_EN: string[] = [
  "Sun",
  "Mon",
  "Tue",
  "Wed",
  "Thu",
  "Fri",
  "Sat",
];

---

WEEK_NP

Full Nepali day names in Devanagari script.

const WEEK_NP: string[] = [
  "आइतबार",
  "सोमबार",
  "मंगलबार",
  "बुधबार",
  "बिहिबार",
  "शुक्रबार",
  "शनिबार",
];

---

WEEK_SHORT_NP

Short Nepali day names.

const WEEK_SHORT_NP: string[] = [
  "आइत",
  "सोम",
  "मंगल",
  "बुध",
  "बिहि",
  "शुक्र",
  "शनि",
];

---

Weekday Reference Table

Index	WEEK_EN	WEEK_SHORT_EN	WEEK_NP	WEEK_SHORT_NP
0	Sunday	Sun	आइतबार	आइत
1	Monday	Mon	सोमबार	सोम
2	Tuesday	Tue	मंगलबार	मंगल
3	Wednesday	Wed	बुधबार	बुध
4	Thursday	Thu	बिहिबार	बिहि
5	Friday	Fri	शुक्रबार	शुक्र
6	Saturday	Sat	शनिबार	शनि

---

Nepali Numbers

NUMBER_NP

Array of Nepali numerals (०-९).

const NUMBER_NP: string[] = ["०", "१", "२", "३", "४", "५", "६", "७", "८", "९"];

Example:

// Convert English number to Nepali
function toNepaliNumber(num: number): string {
  return String(num)
    .split("")
    .map((digit) => NUMBER_NP[parseInt(digit)])
    .join("");
}

console.log(toNepaliNumber(2082)); // '२०८२'
console.log(toNepaliNumber(15)); // '१५'

TIP

The format() method with lowercase tokens automatically uses Nepali numerals:

const date = new NepaliDate(2082, 9, 15);
console.log(date.format("yyyy-mm-dd")); // '२०८२-१०-१५'

---

Date Map

NEPALI_DATE_MAP

Complete mapping of days in each month for years BS 1976-2100.

interface DateMapEntry {
  year: number;
  days: number[]; // Array of 12 month lengths
  totalDays: number; // Total days in the year
  daysTillNow: number; // Cumulative days from BS 2000
}

const NEPALI_DATE_MAP: DateMapEntry[];

Structure:

// Example entries
[
  {
    year: 2000,
    days: [30, 32, 31, 32, 31, 30, 30, 30, 29, 30, 29, 31],
    totalDays: 365,
    daysTillNow: 365,
  },
  {
    year: 2001,
    days: [31, 31, 32, 31, 31, 31, 30, 29, 30, 29, 30, 30],
    totalDays: 365,
    daysTillNow: 730,
  },
  // ... continues to 2100
  {
    year: 2100,
    days: [31, 32, 31, 32, 31, 30, 30, 30, 29, 29, 30, 31],
    totalDays: 366,
    daysTillNow: 36889,
  },
];

Example Usage:

import { NEPALI_DATE_MAP } from "nepali-date-library";

// Get month lengths for a specific year
const year2082 = NEPALI_DATE_MAP.find((entry) => entry.year === 2082);
console.log(year2082?.days);
// [31, 32, 31, 32, 31, 30, 30, 30, 29, 30, 29, 31]

// Days in Magh 2082 (month index 9)
console.log(year2082?.days[9]); // 30

// Total days in 2082
console.log(year2082?.totalDays); // 366

---

Month Length Variations

Nepali months have varying lengths (29-32 days) depending on the year:

Month	Min Days	Max Days	Typical
Baisakh	30	31	31
Jestha	31	32	31-32
Asar	31	32	31-32
Shrawan	31	32	32
Bhadra	31	32	31-32
Aswin	30	31	30-31
Kartik	29	30	29-30
Mangsir	29	30	29-30
Poush	29	30	29-30
Magh	29	30	29-30
Falgun	29	30	29-30
Chaitra	30	31	30-31

WARNING

Never hardcode month lengths! Always use daysInMonth() or the date map to get accurate values.

---

Using Constants for Custom Formatting

import { MONTH_EN, MONTH_NP, WEEK_EN, WEEK_NP } from "nepali-date-library";

function formatDateCustom(date: NepaliDate, nepali: boolean = false): string {
  const months = nepali ? MONTH_NP : MONTH_EN;
  const days = nepali ? WEEK_NP : WEEK_EN;

  return `${days[date.getDay()]}, ${months[date.getMonth()]} ${date.getDate()}, ${date.getYear()}`;
}

const date = new NepaliDate(2082, 9, 15);
console.log(formatDateCustom(date)); // 'Wednesday, Magh 15, 2082'
console.log(formatDateCustom(date, true)); // 'बुधबार, माघ 15, 2082'