Calendar

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ISO weeks, quarters, holidays, and calendar grids

Import

import { ... } from 'ts-time-utils/calendar';

Examples

Week & Quarter

Get week numbers, quarters, and calendar info

import { getWeekNumber, getQuarter, getDaysInMonth, getDaysInYear } from 'ts-time-utils/calendar';

const date = new Date('2025-09-14');

// ISO week number
console.log(getWeekNumber(date)); // 37

// Quarter
console.log(getQuarter(date)); // 3

// Days in month/year
console.log(getDaysInMonth(9, 2025)); // 30
console.log(getDaysInMonth(2, 2024)); // 29 (leap year)
console.log(getDaysInYear(2024)); // 366
console.log(getDaysInYear(2025)); // 365

US Holidays

Calculate US federal holidays

import { getEaster, getUSHolidays, getThanksgivingDay, getMemorialDay } from 'ts-time-utils/calendar';

// Easter (complex calculation!)
console.log(getEaster(2025));

// Get all US holidays for a year
const holidays = getUSHolidays(2025);
holidays.forEach(h => {
  console.log(`${h.name}: ${h.date.toDateString()}`);
});

// Specific holidays
console.log('Thanksgiving 2025:', getThanksgivingDay(2025));
console.log('Memorial Day 2025:', getMemorialDay(2025));