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JavaScript Temporal vs Date

Compare JavaScriptTemporal vs Date.

Learnthe differences in mutation, time zones, DST handling, and date math.

Learn why Temporal is the modern alternative to Date.

Differences Between Date and Temporal

  • Date mixes date and time zone
  • Date parsing is inconsistent
  • Date is 0-based / Temporal is 1-based
  • Date millisecond / Temporal nanosecond

Other Features

FeatureDateTemporal
Created19952026
MutableYesNo (Immutable)
Time Zone SupportLimitedBuilt-in
DTS Safe (Daylight Saving Time)NoYes
Date-Only TypeNoYes
Clear Time TypesNoYes
PrecisitionMillisecondsNanoseconds

Note

The JavaScriptDate object has been used since 1995.

Temporal is the modern replacement designed to fix many of Date's problems.


Mutation vs Immutability

Date objects can change.

This can cause unexpected side effects.

Date Example

// Create a Date
let d = new Date(20126, 5, 1);

// Add 7 days
d.setDate(d.getDate() + 7);

// Here original date is gone
Try it Yourself »

Temporal objects cannot change.

Operations return a new value instead.

Temporal Example

// Create a Date
let d = Temporal.PlainDate.from("2026-05-1");

// Add 7 days
let next = d.add({ days: 7 });

// Here original date is kept
Try it Yourself »

Date and Time Zone

new Date(2026, 4, 1) creates a timestamp of your local time zone at midnight.

This means it can "shift" when you format it in UTC or in another zone.

Example

// Months are 0-based (4 = May)
const d = new Date(2026, 4, 1);

// Might be 2026-04-30T22:00:00.000Z in some time zones:
d.toISOString();
Try it Yourself »

Temporal.PlainDate is not a timestamp.

It is just "2026-05-01" with no time and no time zone, so there can not be any shifting.


Handling Time Zones

Date mixes local time and UTC.

This makes time zone handling confusing.

Date Example

let d = new Date();

console.log(d.toString());
console.log(d.toUTCString());

Temporal uses clear types for time zones.

ZonedDateTime always includes a time zone.

Temporal Example

let zdt = Temporal.Now.zonedDateTimeISO();

console.log(zdt);

Date Parsing is Inconsistent

new Date("2026-05-01") parses as an instant (often treated as UTC by spec in modern JS),but historically it has been a minefield of different formats, browser quirks and locale surprises.

Temporal avoids this by:

  • defining strict parsing rules for ISO strings
  • using Temporal.Instant.from() for clearly-typed conversions

Temporal is 1-Based

  • Date: January = 0
  • Temporal: January = 1 (much more human-friendly)

Example

// May 1:
new Date(2026, 4, 1)

// May 1:
new Temporal.PlainDate(2026, 5, 1)


Date Math

Date math withDate often requires manual calculations.

Date Example

let start = new Date("2026-02-17");
start.setDate(start.getDate() + 30);

console.log(start);

Temporal has built-in date arithmetic.

Temporal Example

let start = Temporal.PlainDate.from("2026-02-17");
let result = start.add({ days: 30 });

console.log(result);

Nanosecond Precision

Unlike the Date object which uses milliseconds, Temporal.Instant offers 1000 times higher nanosecond precision.


Clear Separation of Types

Date represents both a date and a time in one object.

Temporal separates different use cases into different types.

  • Temporal.Instant - Exact moment in time (UTC).

  • Temporal.PlainDate - Date only.

  • Temporal.PlainDateTime - Date and time without time zone.

  • Temporal.ZonedDateTime - Date and time with time zone.

  • Temporal.Duration - Length of time.

This makes code easier to read and less error-prone.


When Should You Use Date?

You may still useDate for simple tasks such as getting a quick timestamp.

You may also need it if you support older environments without Temporal.


When Should You Use Temporal?

  • You need correct time zone handling.

  • You work with international users.

  • You want safe date arithmetic.

  • You want clear and modern code.


Summary

Date works, but it has limitations and confusing behavior.

Temporal is safer, clearer, and designed for modern applications.


Browser Support

Temporal is an ES2026 feature. It is not fully supported in all browsers:

Chrome
144
Edge
144
Firefox
139
Safari
Opera
Jan 2026Jan 2026May 2025🚫🚫



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