This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The getDay() method of Date instances returns the day of the week for this date according to local time, where 0 represents Sunday. For the day of the month, see Date.prototype.getDate().
const birthday = new Date("August 19, 1975 23:15:30");
const day1 = birthday.getDay();
// Sunday - Saturday : 0 - 6
console.log(day1);
// Expected output: 2
getDay()
None.
An integer, between 0 and 6, representing the day of the week for the given date according to local time: 0 for Sunday, 1 for Monday, 2 for Tuesday, and so on. Returns NaN if the date is invalid.
The return value of getDay() is zero-based, which is useful for indexing into arrays of days, for example:
const valentines = new Date("1995-02-14");
const day = valentines.getDay();
const dayNames = ["Sunday", "Monday", "Tuesday" /* , … */];
console.log(dayNames[day]); // "Monday"
However, for the purpose of internationalization, you should prefer using Intl.DateTimeFormat with the options parameter instead.
const options = { weekday: "long" };
console.log(new Intl.DateTimeFormat("en-US", options).format(valentines));
// "Monday"
console.log(new Intl.DateTimeFormat("de-DE", options).format(valentines));
// "Montag"
The weekday variable has value 1, based on the value of the Date object xmas95, because December 25, 1995 is a Monday.
const xmas95 = new Date("1995-12-25T23:15:30");
const weekday = xmas95.getDay();
console.log(weekday); // 1
| Desktop | Mobile | Server | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | Bun | Deno | Node.js | |
getDay |
1 | 12 | 1 | 3 | 1 | 18 | 4 | 10.1 | 1 | 1.0 | 4.4 | 1 | 1.0.0 | 1.0 | 0.10.0 |
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getDay