Date

`Date.prototype.getTime`

Returns the number of milliseconds since January 1, 1970 00:00:00 UTC for the given date

Syntax

JavaScript

date.getTime()

Return Value

A number representing milliseconds since epoch

Examples

Basic Usage

const date = new Date('2024-01-15');
console.log(date.getTime()); // 1705276800000

Practical Example

const d1 = new Date('2024-01-01');
const d2 = new Date('2024-12-31');
const diffDays = (d2.getTime() - d1.getTime()) / (1000 * 60 * 60 * 24);
console.log(diffDays); // 365

Advanced Usage

const date = new Date();
const copy = new Date(date.getTime());
console.log(date.getTime() === copy.getTime()); // true

Understanding Date.prototype.getTime

The Date.prototype.getTime method in JavaScript returns the number of milliseconds since January 1, 1970 00:00:00 UTC for the given date. It belongs to the Date object and is one of the most widely used methods for working with date values in modern JavaScript and TypeScript applications.

The method signature is date.getTime(). When called, it returns a number representing milliseconds since epoch. Understanding when and how to use getTime() helps you write more expressive, readable code.

Common use cases for Date.prototype.getTime include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like date-now, date-parse, date-toisostring, enabling you to chain operations together for complex data manipulation pipelines.

Browser support for Date.prototype.getTime is excellent across all modern browsers including Chrome, Firefox, Safari, and Edge. It is also fully supported in Node.js and Deno. For older environments, transpilation with Babel or a polyfill may be needed.