@qntm-code/utils/dist/mjs/dates/getters/getWeekOfYear.js

A collection of useful utility functions with associated TypeScript types. All functions have been unit tested.

import { TimeUnit, convertTimeUnit } from '../convert-units/index.js';
import { getStartOfYear } from './getStartOfYear.js';
/**
 * Gets the week number of the year for the given date. Will use today's date if no date is provided.
 */
export function getWeekOfYear(date = new Date()) {
    const firstDayOfYear = getStartOfYear(date);
    const offset = firstDayOfYear.getDay() + 1;
    const days = convertTimeUnit(date.getTime() - firstDayOfYear.getTime(), TimeUnit.Milliseconds, TimeUnit.Days);
    return Math.ceil((days + offset) / 7);
}