Intl.DateTimeFormat is used to format date strings in JavaScript.
---
title: JavaScript Intl.DateTimeFormat Cheatsheet
subtitle: Intl.DateTimeFormat is used to format date strings in JavaScript.
author: devhints.io
date: October 8, 2020
source: https://devhints.io/wip/intl-datetime
source2: https://jonlabelle.com/snippets/view/markdown/javascript-intldatetimeformat-cheatsheet
notoc: false
---
## Parsing
As **local** time:
```javascript
const date = new Date(2012, 11, 20, 3, 0, 0);
```
As **UTC** time:
```javascript
const date = new Date(Date.UTC(2012, 11, 20, 3, 0, 0));
```
From **ISO** strings:
```javascript
const date = new Date("2018-04-20T12:00:00Z");
```
> Note that JavaScript doesn't "store" timezones in a date object. All these
> date objects, when expressed via .toString() or similar, will show the local
> timezone of the browser, regardless if you parsed UTC dates.
## Formatting dates
**Default** formatting:
```javascript
console.log(new Intl.DateTimeFormat().format(date));
// '12/19/2012' (assuming America/Los_Angeles)
```
Custom **locale**:
```javascript
console.log(new Intl.DateTimeFormat("en-GB").format(date));
// '19/12/2012' (date-first)
```
Custom **timezone**:
```javascript
console.log(
new Intl.DateTimeFormat("en-AU", {
timeZone: "Australia/Sydney"
}).format(date)
);
// '19/12/2012'
```
## All options
```javascript
{
weekday: 'narrow' | 'short' | 'long',
era: 'narrow' | 'short' | 'long',
year: 'numeric' | '2-digit',
month: 'numeric' | '2-digit' | 'narrow' | 'short' | 'long',
day: 'numeric' | '2-digit',
hour: 'numeric' | '2-digit',
minute: 'numeric' | '2-digit',
second: 'numeric' | '2-digit',
timeZoneName: 'short' | 'long',
// Time zone to express it in
timeZone: 'Asia/Shanghai',
// Force 12-hour or 24-hour
hour12: true | false,
// Rarely-used options
hourCycle: 'h11' | 'h12' | 'h23' | 'h24',
formatMatcher: 'basic' | 'best fit'
}
```
## Custom formats
**Time**:
```javascript
console.log(
new Intl.DateTimeFormat("default", {
hour: "numeric",
minute: "numeric",
second: "numeric"
}).format(date)
);
// '2:00:00 pm'
```
**Date**:
```javascript
console.log(
new Intl.DateTimeFormat("en-US", {
year: "numeric",
month: "numeric",
day: "numeric"
}).format(date)
);
// '12/19/2012'
```
> To specify options without a locale, use 'default' as a locale.
## References
- [MDN Web Docs: Intl.DateTimeFormat](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat)