calendar

Calendar helpers: leap year, week, date math.

Zero dependencies - ~2 KB gzipped - TypeScript - Node + Bun + browser

Install

bun add @knownasrazi/calendar
npm install @knownasrazi/calendar

Usage

import { isLeapYear, daysInMonth, weekNumber, addDays, addMonths, startOfWeek } from "@knownasrazi/calendar";

isLeapYear(2020); // true
daysInMonth(2020, 2); // 29
weekNumber(new Date("2023-01-01")); // ISO week
addDays(new Date("2023-01-01"), 5);
addMonths(new Date("2023-01-31"), 1); // 2023-02-28 (clamped)
startOfWeek(new Date("2023-01-04"), "mon").getDay(); // 1

API

| Export | Description | | --- | --- | | isLeapYear(y) | leap year check | | daysInMonth(y,m) | 28-31 | | weekNumber(date, start?) | ISO week | | addDays/addMonths/addYears(date,n) | date arithmetic | | startOfWeek/endOfWeek(date, start?) | week bounds | | formatISO(date) | YYYY-MM-DD |

Development

git clone https://github.com/knownasrazi/calendar.git
cd calendar
bun install
bun test
bun run build
bun run lint

License

MIT + Razi

calendar - dates without the date-fns.