date-fns vs dayjs vs moment | Date and Time Manipulation Comparison

Package	Downloads	Stars	Size	Issues	Publish	License

date-fns	31,125,286	36,091	22.6 MB	847	a year ago	MIT
dayjs	26,566,267	48,197	672 kB	1,134	9 days ago	MIT
moment	22,994,209	48,094	4.35 MB	293	2 years ago	MIT

Package

Downloads

Stars

Size

Issues

Publish

License

date-fns

31,125,286

36,091

22.6 MB

847

a year ago

MIT

dayjs

26,566,267

48,197

672 kB

1,134

9 days ago

MIT

moment

22,994,209

48,094

4.35 MB

293

2 years ago

MIT

Size and Performance

date-fns:
date-fns is designed to be tree-shakable, meaning you can import only the functions you need, which helps keep your bundle size small. However, the overall size will depend on how many functions you import. It is generally more lightweight than Moment.js but can vary based on usage.
dayjs:
Day.js is significantly smaller in size (about 2KB minified and gzipped), making it a great choice for performance-sensitive applications. Its lightweight nature means faster load times and lower bandwidth usage, which is crucial for mobile applications and sites with many users.
moment:
Moment.js is larger (around 16KB minified and gzipped), which can impact performance, especially in applications where bundle size is a concern. While it offers extensive functionality, the trade-off is a larger footprint that may not be suitable for all projects.

API Design

date-fns:
date-fns provides a functional programming API, which means that each function is standalone and does not require you to create an object to use it. This design promotes immutability and makes it easy to compose functions together. However, it may require more boilerplate code for complex operations compared to object-oriented APIs.
dayjs:
Day.js has a modern and intuitive API that is designed to be chainable and easy to use. It mimics the Moment.js API, making it easy for developers familiar with Moment.js to transition. Its simplicity allows for quick date manipulations without much overhead.
moment:
Moment.js provides a rich API with a wide range of features, including parsing, formatting, and manipulating dates. However, its API can be considered more complex due to the extensive options available, which may lead to a steeper learning curve for new users.

Mutability

date-fns:
date-fns functions are immutable, meaning they do not modify the original date objects. Instead, they return new instances with the changes applied. This immutability helps prevent side effects and makes the code more predictable and easier to debug.
dayjs:
Day.js is immutable, meaning that any operations performed on a Day.js object return a new instance rather than modifying the original object. This immutability helps prevent side effects and makes the code easier to reason about, especially in functional programming contexts.
moment:
Moment.js is mutable, allowing for in-place modifications of date objects. While this can be convenient, it can also lead to unintended side effects if not managed carefully, especially in larger applications where state management is critical.

Localization and Time Zones

date-fns:
date-fns has built-in support for internationalization (i18n) and localization, but it requires you to manually set the locale for each function. This can be a bit cumbersome, but it allows for flexible and accurate localization. Time zone support is limited, and you may need to use additional libraries for more complex time zone manipulations.
dayjs:
Day.js supports localization through plugins, allowing developers to add only the locales they need, which keeps the bundle size small. However, its time zone support is limited compared to Moment.js, requiring additional plugins for full functionality.
moment:
Moment.js has built-in support for localization and time zones, making it a robust choice for applications that require extensive internationalization features. Its comprehensive handling of time zones and formats makes it suitable for applications with complex date and time requirements.

Community and Maintenance

date-fns:
date-fns has a growing community and is actively maintained. Its modular approach and focus on performance have made it a popular choice among developers who prefer a lightweight and functional alternative to Moment.js.
dayjs:
Day.js has a growing community and is actively maintained, with a focus on performance and simplicity. Its modern approach and smaller size have attracted a lot of attention, making it a popular choice for new projects.
moment:
Moment.js has a large and established community, but it is in maintenance mode, meaning that no new features are being added, and the focus is primarily on fixing bugs. This may be a consideration for long-term projects that require ongoing support and updates.

Ease of Use: Code Examples

date-fns:

date-fns example

import { format, addDays } from 'date-fns';

const today = new Date();
const formattedDate = format(today, 'yyyy-MM-dd');
const nextWeek = addDays(today, 7);

console.log(`Today: ${formattedDate}`);
console.log(`Next Week: ${format(nextWeek, 'yyyy-MM-dd')}`);

dayjs:

time zone support in dayjs

import dayjs from 'dayjs';
console.log(dayjs().format('YYYY-MM-DD'));

// Using a plugin
import timezone from 'dayjs/plugin/timezone';
dayjs.extend(timezone);
console.log(dayjs().tz('America/New_York').format());

moment:

time zone support in moment

import moment from 'moment';
console.log(moment().format('YYYY-MM-DD'));

// Using time zone support
import momentTimezone from 'moment-timezone';
console.log(momentTimezone().tz('America/New_York').format());

import { compareAsc, format } from "date-fns"; format(new Date(2014, 1, 11), "yyyy-MM-dd"); //=> '2014-02-11' const dates = [ new Date(1995, 6, 2), new Date(1987, 1, 11), new Date(1989, 6, 10), ]; dates.sort(compareAsc); //=> [ // Wed Feb 11 1987 00:00:00, // Mon Jul 10 1989 00:00:00, // Sun Jul 02 1995 00:00:00 // ]