Nepali Date Library

Overview

The Nepali Date Library (nepali-date-library) is a comprehensive TypeScript/JavaScript library for working with Nepali (Bikram Sambat) dates. It provides a powerful NepaliDate class along with utility functions for date conversion, manipulation, formatting, and more.

What is Bikram Sambat?

Bikram Sambat (BS) is the official calendar of Nepal. It is approximately 56 years and 8 months ahead of the Gregorian calendar (Anno Domini/AD). For example:

• AD 2026-01-14 = BS 2082-10-01
• The Nepali calendar has 12 months with varying lengths (29-32 days)
• The Nepali New Year falls in mid-April (Baisakh 1st)

Key Features

Feature	Description
Date Conversion	Convert between AD and BS dates using ADtoBS() and BStoAD() functions
Date Manipulation	Add or subtract days, months, and years
Formatting	Format dates in both English and Nepali with customizable patterns
Date Comparison	Compare dates, calculate differences, check equality
Date Ranges	Get start/end of day, week, month, or year
Fiscal Year Support	Work with Nepali fiscal years and quarters
Calendar Generation	Generate calendar data for datepicker components
TypeScript Support	Full type definitions included

Supported Date Range

The library supports Nepali dates within the following range:

Calendar	Start	End
Bikram Sambat	1976 Baisakh 1	2100 Chaitra (Last day)
Gregorian (AD)	April 13, 1919	~April 2044

This covers over 125 years of dates with accurate month lengths for each year.

Quick Example

import { NepaliDate, ADtoBS, BStoAD } from "nepali-date-library";

// Create a Nepali date from today
const today = new NepaliDate();

// Get date components
console.log(today.getYear()); // 2082
console.log(today.getMonth()); // 9 (0-indexed, so this is Magh)
console.log(today.getDate()); // 1

// Format the date
console.log(today.format("YYYY-MM-DD")); // 2082-10-01
console.log(today.format("MMMM DD, YYYY")); // Magh 01, 2082
console.log(today.format("yyyy mmmm dd")); // २०८२ माघ ०१

// Convert between calendars
const bs = ADtoBS("2026-01-14"); // '2082-10-01'
const ad = BStoAD("2082-10-01"); // '2026-01-14'

Why Use This Library?

1. Accuracy: Uses a comprehensive date map covering BS 1976-2100 with correct month lengths
2. Full Featured: Not just conversion - includes manipulation, comparison, formatting, and more
3. Localization: Native support for Nepali language and numerals
4. Fiscal Year: Built-in support for Nepal's fiscal year (starts Shrawan 1st)
5. Calendar Ready: Generate complete calendar data for building datepickers
6. TypeScript: Written in TypeScript with full type definitions
7. Updates: We try to update the library every year to cover the latest date range.