Moment.js

Overview

Moment.js is a JavaScript library that facilitates the handling of dates and times within web applications. Since its inception in 2011, it has offered a robust API for tasks such as parsing diverse date string formats, validating dates, performing arithmetic operations on dates (e.g., adding days or subtracting months), and formatting dates into human-readable strings. Its design emphasizes ease of use and flexibility, making it a common choice for projects requiring extensive date manipulation capabilities.

The library addresses common challenges in JavaScript's native Date object, which can be inconsistent across browsers and less intuitive for complex operations. Moment.js provides a consistent interface and a wide array of utility methods to abstract away these complexities, allowing developers to work with dates more efficiently. For instance, it simplifies tasks like determining the difference between two dates, calculating dates relative to the current time, or converting between different time zones.

Moment.js is particularly well-suited for legacy JavaScript projects that already depend on its API, where refactoring to a newer library might be impractical. It excels in scenarios requiring simple date formatting, such as displaying timestamps in a specific locale, and in parsing various input date formats from user entries or external data sources. Its comprehensive parsing capabilities can interpret a wide range of date strings without explicit format definitions, which can be beneficial in less controlled input environments.

However, the maintainers of Moment.js have stated that the project is in maintenance mode and is no longer undergoing active feature development or significant improvements. They recommend that new projects consider modern alternatives like Luxon, date-fns, or Day.js due to Moment.js's mutable nature, larger bundle size, and potential performance implications in modern build environments. The JavaScript ecosystem has evolved to offer more immutable and tree-shakable date libraries that align better with contemporary development practices. For example, the Intl.DateTimeFormat API provides native, performant, and locale-aware date formatting capabilities directly in browsers.

Key features

• Parsing: Interprets various date string formats, JavaScript Date objects, and Unix timestamps into Moment objects. This allows for flexible input handling without explicit format declarations in many cases.
• Validation: Provides methods to check if a given input successfully represents a valid date, which is useful for data integrity and user input validation.
• Manipulation: Offers a range of functions to add, subtract, start of, end of, and clone dates. This enables operations such as finding the date a week from now or the beginning of the current month.
• Formatting: Converts Moment objects into custom string formats using a defined set of tokens. This allows dates to be displayed in specific patterns, such as YYYY-MM-DD or MMMM Do, YYYY.
• Relative Time: Calculates and displays the time difference between a date and the current time in human-readable phrases, like "a few seconds ago" or "in 5 days."
• Duration: Supports operations with durations, allowing developers to represent and manipulate spans of time independently of specific dates.
• Localization: Includes support for multiple locales, enabling date and time formatting to adhere to regional conventions for month names, day names, and relative time phrases.

Pricing

Moment.js is an entirely free and open-source library, distributed under the MIT License. There are no associated costs for its use, redistribution, or modification.

Pricing as of May 7, 2026.

Common integrations

Moment.js is a standalone JavaScript library, and its integration typically involves including it in a project's build process or directly in an HTML file. It can be used alongside various frameworks and libraries:

• React: Integrated into React components for displaying formatted dates or handling date inputs. Examples often involve importing Moment.js and using its methods within component lifecycle methods or event handlers.
• Vue.js: Utilized within Vue components to format and manipulate dates displayed in templates or managed in component data.
• Angular: Employed in Angular applications for date handling in services, components, and pipes to transform date values for display.
• Node.js: Used in server-side applications for date and time processing, such as logging timestamps, managing scheduled tasks, or processing date-related data from databases.
• jQuery: Frequently used in older web applications where jQuery is present, allowing for date operations alongside DOM manipulation.

Alternatives

• Luxon: A modern, immutable, and more performant date and time library designed to address many of Moment.js's architectural limitations.
• date-fns: A modular JavaScript date utility library that offers a functional programming approach, allowing developers to import only the functions they need, leading to smaller bundle sizes.
• Day.js: A minimalist JavaScript library that parses, validates, manipulates, and displays dates and times, designed to be a 2KB alternative with a Moment.js-compatible API.
• Temporal API: A forthcoming JavaScript API intended to provide a modern global standard for date and time handling, aiming to solve many of the issues present in the native Date object and existing libraries.

Getting started

To begin using Moment.js, you can install it via npm or yarn, or include it directly from a CDN. The following example demonstrates basic date formatting and manipulation.

// 1. Install Moment.js (if not using CDN)
// npm install moment
// or
// yarn add moment

// 2. Import Moment.js
import moment from 'moment';

// 3. Get the current date and time
const now = moment();
console.log('Current time:', now.format('MMMM Do YYYY, h:mm:ss a'));
// Example output: "Current time: May 7th 2026, 10:30:45 am"

// 4. Parse a specific date string
const specificDate = moment("2026-01-15 14:30:00");
console.log('Specific date:', specificDate.format('YYYY/MM/DD HH:mm'));
// Example output: "Specific date: 2026/01/15 14:30"

// 5. Add days to a date
const futureDate = now.add(7, 'days');
console.log('One week from now:', futureDate.format('dddd, MMMM Do'));
// Example output: "One week from now: Thursday, May 14th"

// 6. Calculate the difference between two dates
const startDate = moment("2026-04-01");
const endDate = moment("2026-05-07");
const daysDifference = endDate.diff(startDate, 'days');
console.log('Days between dates:', daysDifference);
// Example output: "Days between dates: 36"

// 7. Format using relative time
const pastEvent = moment().subtract(2, 'hours');
console.log('Past event:', pastEvent.fromNow());
// Example output: "Past event: 2 hours ago"