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You-Dont-Need-Momentjs

(★ 13,292)

List of functions which you can use to replace moment.js + ESLint Plugin

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# Installation Guide

1. Get the code

git clone https://github.com/you-dont-need/You-Dont-Need-Momentjs

Downloads the entire project code from GitHub to your computer.

cd You-Dont-Need-Momentjs

Moves into the project folder you just downloaded.

2. Node.js

Easy Recommended

Prerequisites

Git Needed to download the project code from GitHub.
Node.js Node.js must be installed to use npm. The LTS version is recommended.

npm install --save-dev eslint-plugin-you-dont-need-momentjs

Downloads and installs the libraries listed in package.json.

<img src="https://img.shields.io/npm/v/eslint-plugin-you-dont-need-momentjs.svg?style=flat-square"

Type this command into your terminal and run it.

alt="NPM Version">

Type this command into your terminal and run it.

<img src="http://img.shields.io/npm/dm/eslint-plugin-you-dont-need-momentjs.svg?style=flat-square?style=flat-square"

Type this command into your terminal and run it.

✅ After running the command, open the address shown in the terminal (usually something like http://localhost:3000) in your browser.

Pulled directly from this repo's README.

// repository documentation

Was this content helpful?

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# [You don't (may not) need Moment.js](https://you-dont-need.github.io/You-Dont-Need-Momentjs/#/)

[![Join the community on Spectrum](https://withspectrum.github.io/badge/badge.svg)](https://dev.to/t/momentjs)

[Moment.js](https://momentjs.com/) is a fantastic time & date library with lots of great features and utilities. However, if you are working on a performance sensitive web application, it might cause a huge performance overhead because of its complex APIs and large bundle size.

![Large bundle size](https://raw.githubusercontent.com/you-dont-need/You-Dont-Need-Momentjs/master/screenshot.png)

Problems with Moment.js:

- It is highly based on OOP APIs, which makes it fail to work with tree-shaking, thus leading to a huge bundle size and performance issues.
- It is mutable and it causes bugs:
  - [clone](https://momentjs.com/docs/#/parsing/moment-clone/)
  - [How do I work around mutability in moment.js?](https://stackoverflow.com/questions/30979178/how-do-i-work-around-mutability-in-moment-js)
- Complex OOP API (which doubles mutability problem). Here is an example:
  https://github.com/moment/moment/blob/develop/src/test/moment/add_subtract.js#L244-L286
  Moment.js allows to use `a.subtract('ms', 50)`, `a.subtract(50, 'ms')` and even `a.subtract('s', '50')`.

If you are not using timezone but only a few simple functions from moment.js, this might bloat your app, and therefore is considered overkill. [dayjs](https://github.com/iamkun/dayjs) has a smaller core and has very similar APIs so it makes it very easy to migrate. [date-fns](https://github.com/date-fns/date-fns) enables [tree-shaking and other benefits](https://github.com/date-fns/date-fns/issues/275#issuecomment-264934189) so that it works great with React, Sinon.js, and webpack, etc. See https://github.com/moment/moment/issues/2373 for more ideas on why and how people switch from moment.js to other solutions.

## Brief Comparison

| Name      | Tree-shaking | Methods richness | Pattern    | Locale | Timezone Support       | Popularity (stars)                                               | Sizes                                                                                                                        |
| --------- | ------------ | ---------------- | ---------- | ------ | ---------------------- | ---------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------- |
| Moment.js | No           | High             | OO         | 123    | Good (moment-timezone) | ![stars](https://flat.badgen.net/github/stars/moment/moment)     | ![raw](https://flat.badgen.net/bundlephobia/min/moment?label=min) ![size](https://flat.badgen.net/bundlephobia/minzip/moment?label=zip&color=purple)     |
| Luxon     | No           | High             | OO         | -      | Good (Intl)            | ![stars](https://flat.badgen.net/github/stars/moment/luxon)      | ![raw](https://flat.badgen.net/bundlephobia/min/luxon?label=min) ![size](https://flat.badgen.net/bundlephobia/minzip/luxon?label=zip&color=purple)       |
| date-fns  | Yes          | High             | Functional | 64     | Good (date-fns-tz)     | ![stars](https://flat.badgen.net/github/stars/date-fns/date-fns) | ![raw](https://flat.badgen.net/bundlephobia/min/date-fns?label=min) ![size](https://flat.badgen.net/bundlephobia/minzip/date-fns?label=zip&color=purple) |
| dayjs     | No           | High             | OO         | 138    | Good (Intl)            | ![stars](https://flat.badgen.net/github/stars/iamkun/dayjs)      | ![raw](https://flat.badgen.net/bundlephobia/min/dayjs?label=min) ![size](https://flat.badgen.net/bundlephobia/minzip/dayjs?label=zip&color=purple)       |

## Voice of Developers

> [Removed moment.js to replace with date-fns - build output reduced by 40%](https://github.com/oysterprotocol/webnode/pull/116)

> &mdash;<cite>Jared Farago from [webnode](https://github.com/oysterprotocol/webnode/pull/116) project.</cite>

> [Good library if you’re looking to replace Moment.js for one reason or another. Immutable too.](https://twitter.com/dan_abramov/status/805030922785525760)

> &mdash;<cite>Dan Abramov, Author of [Redux](https://github.com/reduxjs/redux) and co-author of [Create React App](https://github.com/facebook/create-react-app). Building tools for humans.</cite>

> [I strongly recommend using date-fns over Moment.js, it's has a nicer API and you can include only parts you need!](https://twitter.com/silvenon/status/804946772690923520)

> &mdash;<cite>Matija Marohnić, a design-savvy frontend developer from Croatia.</cite>

## ESLint Plugin

<p align="center">
  <a href="https://www.npmjs.com/package/eslint-plugin-you-dont-need-momentjs">
    <img src="https://img.shields.io/npm/v/eslint-plugin-you-dont-need-momentjs.svg?style=flat-square"
      alt="NPM Version">
  </a>
  <a href="https://www.npmjs.org/package/eslint-plugin-you-dont-need-momentjs">
    <img src="http://img.shields.io/npm/dm/eslint-plugin-you-dont-need-momentjs.svg?style=flat-square?style=flat-square"
      alt="Downloads">
  </a>
  <a href="https://travis-ci.org/you-dont-need/You-Dont-Need-Momentjs">
    <img src="https://img.shields.io/travis/you-dont-need/You-Dont-Need-Momentjs/master.svg?style=flat-square"
      alt="Build Status">
  </a>
  <a href="https://coveralls.io/github/you-dont-need/You-Dont-Need-Momentjs?branch=master">
    <img src="https://img.shields.io/coveralls/you-dont-need/You-Dont-Need-Momentjs/master.svg?style=flat-square"
      alt="Coverage Status" />
  </a>
</p>

If you're using [ESLint](http://eslint.org/), you can install a
[plugin](http://eslint.org/docs/user-guide/configuring#using-the-configuration-from-a-plugin) that
will help you identify places in your codebase where you don't (may not) need Moment.js.

Install the plugin...

```sh
npm install --save-dev eslint-plugin-you-dont-need-momentjs
```

...then update your config

```js
"extends" : ["plugin:you-dont-need-momentjs/recommended"],
```

## Quick Links

**[Parse](#parse)**

1. [String + Date Format](#string--date-format)
1. [String + Time Format](#string--time-format)
1. [String + Format + locale](#string--format--locale)

**[Get + Set](#get--set)**

1. [Millisecond/Second/Minute/Hour](#millisecond--second--minute--hour)
1. [Date of Month](#date-of-month)
1. [Day of Week](#day-of-week)
1. [Day of Year](#day-of-year)
1. [Week of Year](#week-of-year)
1. [Days in Month](#days-in-month)
1. [Weeks in Year](#weeks-in-year)
1. [Maximum of the given dates](#maximum-of-the-given-dates)
1. [Minimum of the given dates](#minimum-of-the-given-dates)

**[Manipulate](#manipulate)**

1. [Add](#add)
1. [Subtract](#subtract)
1. [Start of Time](#start-of-time)
1. [End of Time](#end-of-time)

**[Display](#display)**

1. [Format](#format)
1. [Time from now](#time-from-now)
1. [Time from X](#time-from-x)
1. [Difference](#difference)

**[Query](#query)**

1. [Is Before](#is-before)
1. [Is Same](#is-same)
1. [Is After](#is-after)
1. [Is Between](#is-between)
1. [Is Leap Year](#is-leap-year)
1. [Is a Date](#is-a-date)

# Feature Parity

⚠️ Indicates other packages or work are needed. See individual functions [above](#quick-links).

|                                | Native | Luxon | date-fns | dayjs | Temporal |
| ------------------------------ | ------ | ----- | -------- | ----- | -------- |
| **Parse**                      |        |       |          |       |          |
| String + Date Format           | ✅     | ✅     | ✅       | ✅    | ✅         |
| String + Time Format           | ✅     | ✅     | ✅       | ⚠️    | ✅        |
| String + Format + locale       | ❌     | ⚠️     | ✅       | ⚠️    | ❌        |
|                                |        |       |          |       |          |
| **Get + Set**                  |        |       |          |       |          |
| Millisecond/Second/Minute/Hour | ✅     | ✅    | ✅       | ✅    | ✅        |
| Date of Month                  | ✅     | ✅    | ✅       | ✅    | ✅        |
| Day of Week                    | ✅     | ✅    | ✅       | ✅    | ✅        |
| Day of Year                    | ✅     | ✅    | ✅       | ✅    | ✅        |
| Week of Year                   | ✅     | ✅    | ✅       | ⚠️    | ✅        |
| Days in Month                  | ✅     | ✅    | ✅       | ✅    | ✅        |
| Weeks in Year                  | ❌     | ❌    | ✅       | ⚠️    | ✅        |
| Maximum of the given dates     | ✅     | ✅    | ✅       | ⚠️    | ✅        |
| Minimum of the given dates     | ✅     | ✅    | ✅       | ⚠️    | ✅        |
|                                |        |       |          |       |          |
| **Manipulate**                 |        |       |          |       |          |
| Add                            | ✅     | ✅    | ✅       | ✅    | ✅        |
| Subtract                       | ✅     | ✅    | ✅       | ✅    | ✅        |
| Start of Time                  | ❌     | ✅    | ✅       | ✅    | ✅        |
| End of Time                    | ✅     | ✅    | ✅       | ✅    | ✅        |
|                                |        |       |          |       |          |
| **Display**                    |        |       |          |       |          |
| Format                         | ✅     | ✅    | ✅       | ✅    | ✅        |
| Time from now                  | ✅     | ❌    | ✅       | ⚠️    | ✅        |
| Time from X                    | ❌     | ❌    | ✅       | ⚠️    | ✅        |
| Difference                     | ✅     | ✅    | ✅       | ✅    | ✅        |
|                                |        |       |          |       |          |
| **Query**                      |        |       |          |       |          |
| Is Before                      | ✅     | ✅    | ✅       | ✅    | ✅        |
| Is Same                        | ✅     | ✅    | ✅       | ✅    | ✅        |
| Is After                       | ✅     | ✅    | ✅       | ✅    | ✅        |
| Is Between                     | ❌     | ✅    | ✅       | ⚠️    | ❌        |
| Is Leap Year                   | ✅     | ✅    | ✅       | ⚠️    | ✅        |
| Is a Date                      | ✅     | ✅    | ✅       | ✅    | ✅        |

## Parse

### String + Date Format

Return the date parsed from date string using the given format string.

```js
// Moment.js
moment('12-25-1995', 'MM-DD-YYYY');
// => "1995-12-24T13:00:00.000Z"

// Native
const datePattern = /^(\d{2})-(\d{2})-(\d{4})$/;
const [, month, day, year] = datePattern.exec('12-25-1995');
new Date(`${month}, ${day} ${year}`);
// => "1995-12-24T13:00:00.000Z"

// date-fns
import parse from 'date-fns/parse';
parse('12-25-1995', 'MM-dd-yyyy', new Date());
// => "1995-12-24T13:00:00.000Z"

// dayjs
dayjs('12-25-1995');
// => "1995-12-24T13:00:00.000Z"

// luxon
DateTime.fromFormat('12-25-1995', 'MM-dd-yyyy').toJSDate();
// => "1995-12-24T13:00:00.000Z"

// Temporal
const datePattern = /^(\d{2})-(\d{2})-(\d{4})$/;
const [, month, day, year] = datePattern.exec('12-25-1995');
new Temporal.ZonedDateTime.from({year, month, day, timeZone: Temporal.Now.timeZone()});
// => "1995-12-24T13:00:00.000Z"
```

**[⬆ back to top](#quick-links)**

### String + Time Format

Return the date parsed from time string using the given format string.

```js
// Moment.js
moment('2010-10-20 4:30', 'YYYY-MM-DD HH:mm');
// => "2010-10-19T17:30:00.000Z"

// Native
const datePattern = /^(\d{4})-(\d{2})-(\d{2})\s(\d{1,2}):(\d{2})$/;
const [, year, month, day, rawHour, min] = datePattern.exec('2010-10-20 4:30');
new Date(`${year}-${month}-${day}T${('0' + rawHour).slice(-2)}:${min}:00`);
// => "2010-10-19T17:30:00.000Z"

// date-fns
import parse from 'date-fns/parse';
parse('2010-10-20 4:30', 'yyyy-MM-dd H:mm', new Date());
// => "2010-10-19T17:30:00.000Z"

// dayjs ⚠️ requires customParseFormat plugin
import customParseFormat from 'dayjs/plugin/customParseFormat';
dayjs.extend(customParseFormat);
dayjs('2010-10-20 4:30', 'YYYY-MM-DD HH:mm');
// => "2010-10-19T17:30:00.000Z"

// luxon
DateTime.fromFormat('2010-10-20 4:30', 'yyyy-MM-dd H:mm').toJSDate();
// => "2010-10-19T17:30:00.000Z"

// Temporal
const datePattern = /^(\d{4})-(\d{2})-(\d{2})\s(\d{1,2}):(\d{2})$/;
const [, year, month, day, hour, minute] = datePattern.exec('2010-10-20 4:30');
new Temporal.ZonedDateTime.from({year, month, day, hour, minute, timeZone: Temporal.Now.timeZone()});
// => "2010-10-19T17:30:00.000Z"
```

**[⬆ back to top](#quick-links)**

### String + Format + locale

Return the date parsed from string using the given format string and locale.

```js
// Moment.js
moment('2012 mars', 'YYYY MMM', 'fr');
// => "2012-02-29T13:00:00.000Z"

// date-fns
import parse from 'date-fns/parse';
import fr from 'date-fns/locale/fr';
parse('2012 mars', 'yyyy MMMM', new Date(), { locale: fr });
// => "2012-02-29T13:00:00.000Z"

// dayjs ⚠️ requires customParseFormat plugin
import customParseFormat from 'dayjs/plugin/customParseFormat';
import 'dayjs/locale/fr';
dayjs.extend(customParseFormat);
dayjs('2012 mars', 'YYYY MMM', 'fr');
// => "2012-02-29T13:00:00.000Z"

// Luxon ❌ does not support Locale for node unless https://moment.github.io/luxon/docs/manual/install.html#node
DateTime.fromFormat('2012 mars', 'yyyy MMMM', { locale: 'fr' });
// => "2012-02-29T13:00:00.000Z"
```

**[⬆ back to top](#quick-links)**

## Get + Set

### Millisecond / Second / Minute / Hour

Get the `Millisecond/Second/Minute/Hour` of the given date.

```js
// Moment.js
moment().seconds();
// => 49
moment().hours();
// => 19

// Native
new Date().getSeconds();
// => 49
new Date().getHours();
// => 19

// date-fns
import getSeconds from 'date-fns/getSeconds';
import getHours from 'date-fns/getHours';
getSeconds(new Date());
// => 49
getHours(new Date());
// => 19

// dayjs
dayjs().second();
// => 49
dayjs().hour();
// => 19

// Luxon
DateTime.local().second;
// => 49
DateTime.local().hour;
// => 19

// Temporal
Temporal.Now.zonedDateTimeISO().second;
// => 49
Temporal.Now.zonedDateTimeISO().hour;
// => 19
```

### Performance tests

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1500.703ms |
| Native   | 348.411ms  |
| DateFns  | 520.670ms  |
| DayJs    | 494.234ms  |
| Luxon    | 1208.368ms |
| Temporal | -          |

Set the `Millisecond/Second/Minute/Hour` of the given date.

```js
// Moment.js
moment().seconds(30);
// => "2018-09-09T09:12:30.695Z"
moment().hours(13);
// => "2018-09-09T03:12:49.695Z"

// Native
new Date(new Date().setSeconds(30));
// => "2018-09-09T09:12:30.695Z"
new Date(new Date().setHours(13));
// => "2018-09-09T03:12:49.695Z"

// date-fns
import setSeconds from 'date-fns/setSeconds';
import setHours from 'date-fns/setHours';
setSeconds(new Date(), 30);
// => "2018-09-09T09:12:30.695Z"
setHours(new Date(), 13);
// => "2018-09-09T03:12:49.695Z"

// dayjs
dayjs().set('second', 30);
// => "2018-09-09T09:12:30.695Z"
dayjs().set('hour', 13);
// => "2018-09-09T03:12:49.695Z"

// luxon
DateTime.utc()
  .set({ second: 30 })
  .toJSDate();
// => "2018-09-09T09:12:30.695Z"
DateTime.utc()
  .set({ hour: 13 })
  .toJSDate();
// => "2018-09-09T03:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().with({ second: 30 });
// => "2018-09-09T09:12:30.695Z"
Temporal.Now.zonedDateTimeISO().with({ hour: 13 });
// => "2018-09-09T03:12:49.695Z"
```

### Performance tests

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1689.744ms |
| Native   | 636.741ms  |
| DateFns  | 714.148ms  |
| DayJs    | 2037.603ms |
| Luxon    | 2897.571ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Date of Month

Gets or sets the day of the month.

```js
// Moment.js
moment().date();
// => 9
moment().date(4);
// => "2018-09-04T09:12:49.695Z"

// Native
new Date().getDate();
// => 9
new Date().setDate(4);
// => "2018-09-04T09:12:49.695Z"

// date-fns
import getDate from 'date-fns/getDate';
import setDate from 'date-fns/setDate';
getDate(new Date());
// => 9
setDate(new Date(), 4);
// => "2018-09-04T09:12:49.695Z"

// dayjs
dayjs().date();
// => 9
dayjs().set('date', 4);
// => "2018-09-04T09:12:49.695Z"

// luxon
DateTime.utc().day;
// => 9
DateTime.utc()
  .set({ day: 4 })
  .toString();
// => "2018-09-04T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().day;
// => 9
Temporal.Now.zonedDateTimeISO().with({ day: 4 });
// => "2018-09-04T09:12:49.695Z"
```

### Performance tests

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1381.669ms |
| Native   | 397.415ms  |
| DateFns  | 588.004ms  |
| DayJs    | 1218.025ms |
| Luxon    | 2705.606ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Day of Week

Gets or sets the day of the week.

```js
// Moment.js
moment().day();
// => 0 (Sunday)
moment().day(-14);
// => "2018-08-26T09:12:49.695Z"

// Native
new Date().getDay();
// => 0 (Sunday)
new Date().setDate(new Date().getDate() - 14);
// => "2018-08-26T09:12:49.695Z"

// date-fns
import getDay from 'date-fns/getDay';
import setDay from 'date-fns/setDay';
getDay(new Date());
// => 0 (Sunday)
setDay(new Date(), -14);
// => "2018-08-26T09:12:49.695Z"

// dayjs
dayjs().day();
// => 0 (Sunday)
dayjs().set('day', -14);
// => "2018-08-26T09:12:49.695Z"

// Luxon
DateTime.local().weekday;
// => 7 (Sunday)
DateTime.local()
  .minus({ day: 14 })
  .toJSDate();
// => "2018-08-26T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().dayOfWeek;
// => 7 (Sunday)
Temporal.Now.zonedDateTimeISO().subtract(Temporal.Duration.from({ days: 14 }));
// => "2018-09-04T09:12:49.695Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1919.404ms |
| Native   | 543.466ms  |
| DateFns  | 841.436ms  |
| DayJs    | 1229.475ms |
| Luxon    | 3936.282ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Day of Year

Gets or sets the day of the year.

```js
// Moment.js
moment().dayOfYear();
// => 252
moment().dayOfYear(256);
// => "2018-09-13T09:12:49.695Z"

// Native
Math.floor(
  (new Date() - new Date(new Date().getFullYear(), 0, 0)) / 1000 / 60 / 60 / 24
);
// => 252

// date-fns
import getDayOfYear from 'date-fns/getDayOfYear';
import setDayOfYear from 'date-fns/setDayOfYear';
getDayOfYear(new Date());
// => 252
setDayOfYear(new Date(), 256);
// => "2018-09-13T09:12:49.695Z"

// dayjs ⚠️ requires dayOfYear plugin
import dayOfYear from 'dayjs/plugin/dayOfYear';
dayjs.extend(dayOfYear);
dayjs().dayOfYear();
// => 252
dayjs().dayOfYear(256);
// => "2018-09-13T09:12:49.695Z"

// Luxon
DateTime.local().ordinal;
// => 252
DateTime.local()
  .set({ ordinal: 256 })
  .toString();
// => "2018-09-13T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().dayOfYear;
// => 252
Temporal.Now.zonedDateTimeISO().with({month: 1, day: 1}).add(Temporal.Duration.from({days: 256}));
// => "2018-09-04T09:12:49.695Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 5511.172ms |
| Native   | 530.592ms  |
| DateFns  | 2079.043ms |
| DayJs    | -          |
| Luxon    | 3540.810ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Week of Year

Gets or sets the week of the year.

```js
// Moment.js
moment().week();
// => 37
moment().week(24);
// => "2018-06-10T09:12:49.695Z"

// date-fns
import getWeek from 'date-fns/getWeek';
import setWeek from 'date-fns/setWeek';
getWeek(new Date());
// => 37
setWeek(new Date(), 24);
// => "2018-06-10T09:12:49.695Z"

// native getWeek
const day = new Date();
const MILLISECONDS_IN_WEEK = 604800000;
const firstDayOfWeek = 1; // monday as the first day (0 = sunday)
const startOfYear = new Date(day.getFullYear(), 0, 1);
startOfYear.setDate(
  startOfYear.getDate() + (firstDayOfWeek - (startOfYear.getDay() % 7))
);
const dayWeek = Math.round((day - startOfYear) / MILLISECONDS_IN_WEEK) + 1;
// => 37

// native setWeek
const day = new Date();
const week = 24;
const MILLISECONDS_IN_WEEK = 604800000;
const firstDayOfWeek = 1; // monday as the first day (0 = sunday)
const startOfYear = new Date(day.getFullYear(), 0, 1);
startOfYear.setDate(
  startOfYear.getDate() + (firstDayOfWeek - (startOfYear.getDay() % 7))
);
const dayWeek = Math.round((day - startOfYear) / MILLISECONDS_IN_WEEK) + 1;
day.setDate(day.getDate() - (dayWeek - week) * 7);
day.toISOString();
// => "2018-06-10T09:12:49.794Z

// dayjs ⚠️ requires weekOfYear plugin
import weekOfYear from 'dayjs/plugin/weekOfYear';
dayjs.extend(weekOfYear);
dayjs().week();
// => 37
dayjs().week(24);
// => "2018-06-10T09:12:49.695Z"

// Luxon
DateTime.local().weekNumber;
// => 37
DateTime.local()
  .set({ weekNumber: 23 })
  .toString();
// => "2018-06-10T09:12:49.794Z

// Temporal
Temporal.Now.zonedDateTimeISO().weekOfYear;
// => 252
Temporal.Now.zonedDateTimeISO().with({month: 1, day: 1}).add(Temporal.Duration.from({weeks: 23}));
// => "2018-09-04T09:12:49.695Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 7147.201ms |
| Native   | 1371.631ms |
| DateFns  | 5834.815ms |
| DayJs    | -          |
| Luxon    | 4514.771ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Days in Month

Get the number of days in the current month.

```js
// Moment.js
moment('2012-02', 'YYYY-MM').daysInMonth();
// => 29

// Native
new Date(2012, 02, 0).getDate();
// => 29

// date-fns
import getDaysInMonth from 'date-fns/getDaysInMonth';
getDaysInMonth(new Date(2012, 1));
// => 29

// dayjs
dayjs('2012-02').daysInMonth();
// => 29

// Luxon
DateTime.local(2012, 2).daysInMonth;
// => 29

// Temporal
(new Temporal.PlainYearMonth(2012, 2)).daysInMonth
// or
Temporal.PlainYearMonth.from('2012-02').daysInMonth
// => 29
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 4415.065ms |
| Native   | 186.196ms  |
| DateFns  | 634.084ms  |
| DayJs    | 1922.774ms |
| Luxon    | 1403.032ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Weeks in Year

Gets the number of weeks in the current year, according to ISO weeks.

```js
// Moment.js
moment().isoWeeksInYear();
// => 52

// Native
const year = new Date().getFullYear();
const MILLISECONDS_IN_WEEK = 604800000;
const firstMondayThisYear = new Date(+year,   0, 5-(new Date(+year,   0, 4).getDay()||7));
const firstMondayNextYear = new Date(+year+1, 0, 5-(new Date(+year+1, 0, 4).getDay()||7));
(firstMondayNextYear - firstMondayThisYear) / MILLISECONDS_IN_WEEK;
// => 52

// date-fns
import getISOWeeksInYear from 'date-fns/getISOWeeksInYear';
getISOWeeksInYear(new Date());
// => 52

// dayjs ⚠️ requires isoWeeksInYear plugin
import isoWeeksInYear from 'dayjs/plugin/isoWeeksInYear';
dayjs.extend(isoWeeksInYear);
dayjs().isoWeeksInYear();
// => 52

// Luxon
DateTime.local().weeksInWeekYear;
// => 52

// Temporal
Temporal.PlainDate.from({day:31, month:12, year: Temporal.Now.plainDateISO()}).weekOfYear
// => 52
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1065.247ms |
| Native   | -          |
| DateFns  | 4954.042ms |
| DayJs    | -          |
| Luxon    | 1134.483ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Maximum of the given dates

Returns the maximum (most distant future) of the given date.

```js
const array = [
  new Date(2017, 4, 13),
  new Date(2018, 2, 12),
  new Date(2016, 0, 10),
  new Date(2016, 0, 9),
];
// Moment.js
moment.max(array.map(a => moment(a)));
// => "2018-03-11T13:00:00.000Z"

// Native
new Date(Math.max.apply(null, array)).toISOString();
// => "2018-03-11T13:00:00.000Z"

// date-fns
import max from 'date-fns/max';
max(array);
// => "2018-03-11T13:00:00.000Z"

// dayjs ⚠️ requires minMax plugin
import minMax from 'dayjs/plugin/minMax';
dayjs.extend(minMax);
dayjs.max(array.map(a => dayjs(a)));
// => "2018-03-11T13:00:00.000Z"

// Luxon
DateTime.max(...array.map(a => DateTime.fromJSDate(a))).toJSDate();
// => "2018-03-11T13:00:00.000Z"

// Temporal
Temporal.Instant.fromEpochMilliseconds(Math.max.apply(null, array))
// => "2018-03-11T13:00:00.000Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1780.075ms |
| Native   | 828.332ms  |
| DateFns  | 980.938ms  |
| DayJs    | -          |
| Luxon    | 2694.702ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Minimum of the given dates

Returns the minimum (most distant future) of the given date.

```js
const array = [
  new Date(2017, 4, 13),
  new Date(2018, 2, 12),
  new Date(2016, 0, 10),
  new Date(2016, 0, 9),
];
// Moment.js
moment.min(array.map(a => moment(a)));
// => "2016-01-08T13:00:00.000Z"

// Native
new Date(Math.min.apply(null, array)).toISOString();
// => "2016-01-08T13:00:00.000Z"

// date-fns
import min from 'date-fns/min';
min(array);
// => "2016-01-08T13:00:00.000Z"

// dayjs ⚠️ requires minMax plugin
import minMax from 'dayjs/plugin/minMax';
dayjs.extend(minMax);
dayjs.min(array.map(a => dayjs(a)));
// => "2016-01-08T13:00:00.000Z"

// Luxon
DateTime.min(...array.map(a => DateTime.fromJSDate(a))).toJSDate();
// => "2016-01-08T13:00:00.000Z"

// Temporal
Temporal.Instant.fromEpochMilliseconds(Math.min.apply(null, array))
// => "2018-03-11T13:00:00.000Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1744.459ms |
| Native   | 819.646ms  |
| DateFns  | 841.249ms  |
| DayJs    | -          |
| Luxon    | 2720.462ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

## Manipulate

### Add

Add the specified number of days to the given date.

```js
// Moment.js
moment().add(7, 'days');
// => "2018-09-16T09:12:49.695Z"

// Native
const now = new Date();
now.setDate(now.getDate() + 7);
// => "Sun Sep 16 2018 09:12:49"

// date-fns
import addDays from 'date-fns/addDays';
addDays(new Date(), 7);
// => "2018-09-16T09:12:49.695Z"

// dayjs
dayjs().add(7, 'day');
// => "2018-09-16T09:12:49.695Z"

// Luxon
DateTime.local()
  .plus({ day: 7 })
  .toJSDate();
// => "2018-09-16T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().add(Temporal.Duration.from({days: 7}));
// => "2018-09-16T09:12:49.695Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1309.485ms |
| Native   | 259.932ms  |
| DateFns  | 385.394ms  |
| DayJs    | 1911.881ms |
| Luxon    | 3919.797ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Subtract

Subtract the specified number of days from the given date.

```js
// Moment.js
moment().subtract(7, 'days');
// => "2018-09-02T09:12:49.695Z"

// Native
const now = new Date();
now.setDate(now.getDate() - 7);
// => Sun Sep 09 2018 09:12:49

// date-fns
import subDays from 'date-fns/subDays';
subDays(new Date(), 7);
// => "2018-09-02T09:12:49.695Z"

// dayjs
dayjs().subtract(7, 'day');
// => "2018-09-02T09:12:49.695Z"

// Luxon
DateTime.local()
  .minus({ day: 7 })
  .toJSDate();
// => "2018-09-02T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().subtract(Temporal.Duration.from({days: 7}));
// => "2018-09-02T09:12:49.695Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1278.384ms |
| Native   | 215.255ms  |
| DateFns  | 379.057ms  |
| DayJs    | 1772.593ms |
| Luxon    | 4028.866ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### Start of Time

Return the start of a unit of time for the given date.

```js
// Moment.js
moment().startOf('month');
// => "2018-08-31T14:00:00.000Z"

// date-fns
import startOfMonth from 'date-fns/startOfMonth';
startOfMonth(new Date());
// => "2018-08-31T14:00:00.000Z"

// dayjs
dayjs().startOf('month');
// => "2018-08-31T14:00:00.000Z"

// Luxon
DateTime.local().startOf('month');
// => "2018-09-02T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().with({day: 1});
// => "2018-09-01T14:00:00.000Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1078.948ms |
| Native   | -          |
| DateFns  | 398.107ms  |
| DayJs    | 765.358ms  |
| Luxon    | 2306.765ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

### End of Time

Return the end of a unit of time for the given date.

```js
// Moment.js
moment().endOf('day');
// => "2018-09-09T13:59:59.999Z"

// Native
const end = new Date();
end.setHours(23, 59, 59, 999);
end.toISOString();
// => "2018-09-09T16:59:59.999Z"

// date-fns
import endOfDay from 'date-fns/endOfDay';
endOfDay(new Date());
// => "2018-09-09T13:59:59.999Z"

// dayjs
dayjs().endOf('day');
// => "2018-09-09T13:59:59.999Z"

// Luxon
DateTime.local().endOf('day');
// => "2018-09-02T09:12:49.695Z"

// Temporal
Temporal.Now.zonedDateTimeISO().withPlainTime(new Temporal.PlainTime(23,59,59,999,999,999));
// => "2018-09-09T16:59:59.999999999Z"
```

| Library  | Time       |
| -------- | ---------- |
| Moment   | 1241.304ms |
| Native   | 225.519ms  |
| DateFns  | 319.773ms  |
| DayJs    | 914.425ms  |
| Luxon    | 9920.529ms |
| Temporal | -          |

**[⬆ back to top](#quick-links)**

## Display

### Format

Return the formatted date string in the given format.

```js
// Moment.js
moment().format('dddd, MMMM Do YYYY, h:mm:ss A');
// => "Sunday, September 9th 2018, 7:12:49 PM"
moment().format('ddd, hA');
// => "Sun, 7PM"

// Native
new Intl.DateTimeFormat('en-US', { dateStyle: 'full', timeStyle: 'medium' }).format(new Date())
// => "Sunday, September 9, 2018 at 7:12:49 PM"
new Intl.DateTimeFormat('en-US', { weekday: 'short', hour: 'numeric' }).format(new Date())
// => "Sun, 7 PM"

// date-fns
import { intlFormat } from 'date-fns'
intlFormat(new Date(), { dateStyle: 'full', timeStyle: 'medium' }, { locale: 'en-US', })
// => "Sunday, September 9, 2018 at 7:12:49 PM"
intlFormat(new Date(), { weekday: 'short', hour: 'numeric' }, { locale: 'en-US', })
// => "Sun, 7 PM"

// dayjs
dayjs().format('dddd, MMMM D YYYY, h:mm:ss A');
// => "Sunday, September 9 2018, 7:12:49 PM"
dayjs().format('ddd, hA');
// => "Sun, 7PM"
// dayjs ⚠️ requires advancedFormat plugin to support more format tokens
import advancedFormat from 'dayjs/plugin/advancedFormat';
dayjs.extend(advancedFormat);
dayjs().format('dddd, MMMM Do YYYY, h:mm:ss A');
// => "Sunday, September 9th 2018, 7:12:49 PM"

// Luxon
DateTime.fromMillis(time).toFormat('EEEE, MMMM dd yyyy, h:mm:ss a');
// => "Sunday, September 9 2018, 7:12:49 PM" ⚠️  not support 9th
DateTime.fromMillis(time).toFormat('EEE, ha');
// => "Sun, 7PM"

// Temporal
new Intl.DateTimeFormat('en-US', { dateStyle: 'full', timeStyle: 'medium' }).format(Temporal.Now.zonedDateTimeISO())
// => "Sunday, September 9, 2018 at 7:12:49 PM"
new Intl.DateTimeFormat('en-US', { weekday: 'short', hour: 'numeric' }).format(Temporal.Now.zonedDateTimeISO())
// => "Sun, 7 PM"
```

**[⬆ back to top](#quick-links)**

### Time from now

Return time from now.

```js
// Moment.js
moment(1536484369695).fromNow();
// => "4 days ago"

// Native
new Intl.RelativeTimeFormat().format(-4, 'day');
// => "4 days ago"

// date-fns
import formatDistance from 'date-fns/formatDistance';
formatDistance(new Date(1536484369695), new Date(), { addSuffix: true });
// => "4 days ago"

// dayjs ⚠️ requires relativeTime plugin
import relativeTime from 'dayjs/plugin/relativeTime';
dayjs.extend(relativeTime);

dayjs(1536484369695).fromNow();
// => "5 days ago" ⚠️  the rounding method of this plugin is different from moment.js and date-fns, use with care.

// luxon requires Intl.RelativeTimeFormat
DateTime.local(2022, 1, 27).toRelative({ base: this })
// => "in 4 months"

// Temporal
new Intl.RelativeTimeFormat().format(-4, 'day');
// => "4 days ago"
```

**[⬆ back to top](#quick-links)**

### Time from x

Return time from x.

```js
// Moment.js
moment([2007, 0, 27]).to(moment([2007, 0, 29]));
// => "in 2 days"

// date-fns
import formatDistance from 'date-fns/formatDistance';
formatDistance(new Date(2007, 0, 27), new Date(2007, 0, 29));
// => "2 days"

// dayjs ⚠️ requires relativeTime plugin
import relativeTime from 'dayjs/plugin/relativeTime';
dayjs.extend(relativeTime);
dayjs('2007-01-27').to(dayjs('2007-01-29'));
// => "in 2 days"

// luxon ❌ does not support relative time

// Temporal
Temporal.PlainDate.from('2007-01-27').until('2007-01-29');
// => Temporal.Duration('P2D')
```

**[⬆ back to top](#quick-links)**

### Difference

Get the unit of time between the given dates.

```js
// Moment.js
moment([2007, 0, 27]).diff(moment([2007, 0, 29]));
// => -172800000
moment([2007, 0, 27]).diff(moment([2007, 0, 29]), 'days');
// => -2

// Native
new Date(2007, 0, 27) - new Date(2007, 0, 29);
// => -172800000
Math.ceil(
  (new Date(2007, 0, 27) - new Date(2007, 0, 29)) / 1000 / 60 / 60 / 24
);
// => -2

// date-fns
import differenceInMilliseconds from 'date-fns/differenceInMilliseconds';
differenceInMilliseconds(new Date(2007, 0, 27), new Date(2007, 0, 29));
// => -172800000
import differenceInDays from 'date-fns/differenceInDays';
differenceInDays(new Date(2007, 0, 27), new Date(2007, 0, 29));
// => -2

// dayjs
dayjs('2007-01-27').diff(dayjs('2007-01-29'), 'milliseconds');
// => -172800000
dayjs('2007-01-27').diff(dayjs('2007-01-29'), 'days');
// => -2

// luxon
DateTime.local(2007, 1, 27).diff(DateTime.local(2007, 1, 29)).milliseconds;
// => -172800000
DateTime.local(2007, 1, 27).diff(DateTime.local(2007, 1, 29), 'days').days;
// => -2

// Temporal
Temporal.PlainDate.from('2007-01-27').since('2007-01-29').total({unit: 'millisecond'});
// => -172800000
Temporal.PlainDate.from('2007-01-27').since('2007-01-29').total({unit: 'day'});
// => -2
```

**[⬆ back to top](#quick-links)**

## Query

### Is Before

Check if a date is before another date.

```js
// Moment.js
moment('2010-10-20').isBefore('2010-10-21');
// => true

// Native
new Date(2010, 10, 20) < new Date(2010, 10, 21);
// => true

// date-fns
import isBefore from 'date-fns/isBefore';
isBefore(new Date(2010, 9, 20), new Date(2010, 9, 21));
// => true

// dayjs
dayjs('2010-10-20').isBefore('2010-10-21');
// => true

// luxon
DateTime.fromISO('2010-10-20') < DateTime.fromISO('2010-10-21');
// => true

// Temporal
Temporal.PlainDate.compare('2010-10-20', '2010-10-21') === -1;
// => true
```

**[⬆ back to top](#quick-links)**

### Is Same

Check if a date is the same as another date.

```js
// Moment.js
moment('2010-10-20').isSame('2010-10-21');
// => false
moment('2010-10-20').isSame('2010-10-20');
// => true
moment('2010-10-20').isSame('2010-10-21', 'month');
// => true

// Native
new Date(2010, 9, 20).valueOf() === new Date(2010, 9, 21).valueOf();
// => false
new Date(2010, 9, 20).valueOf() === new Date(2010, 9, 20).valueOf();
// => true
new Date(2010, 9, 20).getTime() === new Date(2010, 9, 20).getTime();
// => true
new Date(2010, 9, 20).valueOf() === new Date(2010, 9, 20).getTime();
// => true
new Date(2010, 9, 20).toDateString().substring(4, 7) ===
  new Date(2010, 9, 21).toDateString().substring(4, 7);
// => true

// date-fns
import isSameDay from 'date-fns/isSameDay';
import isSameMonth from 'date-fns/isSameMonth';
isSameDay(new Date(2010, 9, 20), new Date(2010, 9, 21));
// => false
isSameDay(new Date(2010, 9, 20), new Date(2010, 9, 20));
// => true
isSameMonth(new Date(2010, 9, 20), new Date(2010, 9, 21));
// => true

// dayjs
dayjs('2010-10-20').isSame('2010-10-21');
// => false
dayjs('2010-10-20').isSame('2010-10-20');
// => true
dayjs('2010-10-20').isSame('2010-10-21', 'month');
// => true

// luxon
(+DateTime.fromISO('2010-10-20') ===
  +DateTime.fromISO('2010-10-21') +
    // => false
    DateTime.fromISO('2010-10-20')) ===
  +DateTime.fromISO('2010-10-20');
// => true
DateTime.fromISO('2010-10-20').hasSame(DateTime.fromISO('2010-10-21'), 'month');
// => true

// Temporal
Temporal.PlainDate.from('2010-10-20').equals('2010-10-21');
// => false
Temporal.PlainDate.from('2010-10-20').equals('2010-10-20');
// => true
Temporal.PlainDate.from('2010-10-20').month === Temporal.PlainDate.from('2010-10-21').month;
// => true
```

**[⬆ back to top](#quick-links)**

### Is After

Check if a date is after another date.

```js
// Moment.js
moment('2010-10-20').isAfter('2010-10-19');
// => true

// Native
new Date(2010, 9, 20) > new Date(2010, 9, 19);
// => true

// date-fns
import isAfter from 'date-fns/isAfter';
isAfter(new Date(2010, 9, 20), new Date(2010, 9, 19));
// => true

// dayjs
dayjs('2010-10-20').isAfter('2010-10-19');
// => true

// luxon
DateTime.fromISO('2010-10-20') > DateTime.fromISO('2010-10-19');
// => true

// Temporal
Temporal.PlainDate.compare('2010-10-20', '2010-10-19') === 1;
// => true
```

**[⬆ back to top](#quick-links)**

### Is Between

Check if a date is between two other dates.

```js
// Moment.js
moment('2010-10-20').isBetween('2010-10-19', '2010-10-25');
// => true

// date-fns
import isWithinInterval from 'date-fns/isWithinInterval';
isWithinInterval(new Date(2010, 9, 20), {
  start: new Date(2010, 9, 19),
  end: new Date(2010, 9, 25),
});
// => true

// dayjs ⚠️ requires isBetween plugin
import isBetween from 'dayjs/plugin/isBetween';
dayjs.extend(isBetween);
dayjs('2010-10-20').isBetween('2010-10-19', '2010-10-25');
// => true

// luxon
Interval.fromDateTimes(
  DateTime.fromISO('2010-10-19'),
  DateTime.fromISO('2010-10-25')
).contains(DateTime.fromISO('2010-10-20'));
// => true
```

**[⬆ back to top](#quick-links)**

### Is Leap Year

Check if a year is a leap year.

```js
// Moment.js
moment([2000]).isLeapYear();
// => true

// Native
new Date(2000, 1, 29).getDate() === 29;
// => true

// date-fns
import isLeapYear from 'date-fns/isLeapYear';
isLeapYear(new Date(2000, 0, 1));
// => true

// dayjs ⚠️ requires isLeapYear plugin
import isLeapYear from 'dayjs/plugin/isLeapYear';
dayjs.extend(isLeapYear);
dayjs('2000-01-01').isLeapYear();
// => true

// luxon
expect(DateTime.local(2000).isInLeapYear).toBeTruthy();
// => true

// Temporal
Temporal.PlainDate.from('2000-01-01').inLeapYear;
// => true
```

**[⬆ back to top](#quick-links)**

### Is a Date

Check if a variable is a native js Date object.

```js
// Moment.js
moment.isDate(new Date());
// => true

// Native
new Date() instanceof Date;
// => true

// date-fns
import isDate from 'date-fns/isDate';
isDate(new Date());
// => true

// dayjs
dayjs(new Date()).isValid();

// luxon
DateTime.local().isValid;
// => true

// Temporal
new Date() instanceof Date;
Temporal.Now.plainTimeISO() instanceof Temporal.PlainTime;
Temporal.Now.plainDateISO() instanceof Temporal.PlainDate;
Temporal.Now.plainDateTimeISO() instanceof Temporal.PlainDateTime;
Temporal.Now.zonedDateTimeISO() instanceof Temporal.ZonedDateTime;
// => true
```

**[⬆ back to top](#quick-links)**

# License

MIT