Introduction

JavaScript’s Date object has been around since 1997, and it’s... well, let’s say, quirky. From inconsistent time zone handling to confusing zero-based months, developers have long struggled with the limitations and odd behaviors of the Date API.

Enter Temporal, a modern date-time API designed to fix the long-standing problems of Date and provide a robust, accurate, and extensible standard for date and time manipulation.

In this article, we’ll explore:

• Why Date is flawed

• What Temporal is

• How to use Temporal with real-world examples

• How it compares to libraries like Moment.js or date-fns

• Migration tips

🚨 What's Wrong with Date?

Before we dive into Temporal, let’s recap some of the problems with the built-in Date object:

❌ 1. Mutability

const date = new Date();
date.setFullYear(2000);
console.log(date); // Mutated object

❌ 2. Time zone confusion

const date = new Date('2025-04-06');
console.log(date.toString()); // Local timezone
console.log(date.toUTCString()); // UTC

❌ 3. Inconsistent parsing

new Date('2025-04-06'); // Works
new Date('2025-04-06T25:00'); // Invalid in some browsers

❌ 4. Zero-based months

new Date(2025, 3, 6); // April 6, NOT March 6

❌ 5. No real support for calendars or durations

🌟 Meet Temporal: The New Date-Time API

Temporal is a Stage 3 proposal (as of 2025) to replace Date with a new standard API. It was created by TC39, the JavaScript standards committee, to:

• Provide better accuracy

• Improve readability and usability

• Support time zones and calendars

• Be immutable and chainable

🧰 Temporal's Core Types

✍️ Real-World Examples

✅ Create a Date

const date = Temporal.PlainDate.from('2025-04-06');
console.log(date.toString()); // "2025-04-06"

✅ Create a DateTime

const dateTime = Temporal.PlainDateTime.from('2025-04-06T14:30');
console.log(dateTime.toString()); // "2025-04-06T14:30"

✅ Create a ZonedDateTime

const zoned = Temporal.ZonedDateTime.from('2025-04-06T14:30[Asia/Kolkata]');
console.log(zoned.toString()); // "2025-04-06T14:30+05:30[Asia/Kolkata]"

✅ Current Date and Time

const now = Temporal.Now.plainDateTimeISO();
console.log(now.toString());

✅ Add/Subtract Dates (immutably!)

const today = Temporal.PlainDate.from('2025-04-06');
const nextWeek = today.add({ days: 7 });
console.log(nextWeek.toString()); // "2025-04-13"

const yesterday = today.subtract({ days: 1 });
console.log(yesterday.toString()); // "2025-04-05"

✅ Difference Between Two Dates

const start = Temporal.PlainDate.from('2025-04-01');
const end = Temporal.PlainDate.from('2025-04-06');
const diff = end.since(start);
console.log(diff.days); // 5

✅ Duration Arithmetic

const duration = Temporal.Duration.from({ hours: 2, minutes: 30 });
const added = duration.add({ minutes: 45 });
console.log(added.toString()); // "PT3H15M"

✅ Convert Between Time Zones

const instant = Temporal.Now.instant();
const nyTime = instant.toZonedDateTimeISO('America/New_York');
const tokyoTime = instant.toZonedDateTimeISO('Asia/Tokyo');

console.log(nyTime.toString());
console.log(tokyoTime.toString());

✅ Get Parts of a Date

const date = Temporal.PlainDate.from('2025-04-06');
console.log(date.year);  // 2025
console.log(date.month); // 4
console.log(date.day);   // 6

🔪 Comparison with Moment.js / date-fns

Note: While Moment.js and date-fns are still great libraries, Temporal is designed to be the future of date-time in JavaScript, providing consistency and precision out-of-the-box.

🚀 Migrating from Date to Temporal

Convert Date to Temporal.Instant

const date = new Date();
const instant = Temporal.Instant.fromEpochMilliseconds(date.getTime());
console.log(instant.toString());

Convert Temporal to native Date (if needed)

const instant = Temporal.Now.instant();
const date = new Date(instant.epochMilliseconds);

⚠️ Browser Support

As of 2025, Temporal is available in most modern environments behind a flag or via a polyfill. To use it today, you can install:

npm install @js-temporal/polyfill

Then import and use:

import { Temporal } from '@js-temporal/polyfill';

🧠 Final Thoughts

Temporal is powerful, predictable, and precise. It’s solving decades of developer frustration with the native Date API and modernizing how we work with time in JavaScript.

💡 Whether you're building calendars, handling time zones, or just calculating someone’s age correctly, Temporal is the future.

🛠️ TL;DR – When to Use What?