File size: 2,284 Bytes
780c9fe | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 | ---
title: Date.prototype.getDay()
short-title: getDay()
slug: Web/JavaScript/Reference/Global_Objects/Date/getDay
page-type: javascript-instance-method
browser-compat: javascript.builtins.Date.getDay
sidebar: jsref
---
The **`getDay()`** method of {{jsxref("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 {{jsxref("Date.prototype.getDate()")}}.
{{InteractiveExample("JavaScript Demo: Date.prototype.getDay()", "shorter")}}
```js interactive-example
const birthday = new Date("August 19, 1975 23:15:30");
const day1 = birthday.getDay();
// Sunday - Saturday : 0 - 6
console.log(day1);
// Expected output: 2
```
## Syntax
```js-nolint
getDay()
```
### Parameters
None.
### Return value
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](/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date#the_epoch_timestamps_and_invalid_date).
## Description
The return value of `getDay()` is zero-based, which is useful for indexing into arrays of days, for example:
```js
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 {{jsxref("Intl.DateTimeFormat")}} with the `options` parameter instead.
```js
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"
```
## Examples
### Using getDay()
The `weekday` variable has value `1`, based on the value of the {{jsxref("Date")}} object `xmas95`, because December 25, 1995 is a Monday.
```js
const xmas95 = new Date("1995-12-25T23:15:30");
const weekday = xmas95.getDay();
console.log(weekday); // 1
```
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{jsxref("Date.prototype.getUTCDate()")}}
- {{jsxref("Date.prototype.getUTCDay()")}}
- {{jsxref("Date.prototype.setDate()")}}
|