Intl.DateTimeFormat

Intl.DateTimeFormat.prototype.resolvedOptions

Returns a new object with properties reflecting the locale and date/time formatting options computed during initialization

Syntax

JavaScript
dateTimeFormat.resolvedOptions()

Return Value

An object with resolved locale and formatting options

Examples

Basic Usage
const fmt = new Intl.DateTimeFormat('en-US', { dateStyle: 'full' })
const opts = fmt.resolvedOptions()
console.log(opts.locale, opts.calendar, opts.timeZone)
Practical Example
function getUserTimezone(): string {
  return new Intl.DateTimeFormat().resolvedOptions().timeZone
}
Advanced Usage
const fmt = new Intl.DateTimeFormat('ja-JP-u-ca-japanese')
const { calendar, locale } = fmt.resolvedOptions()
console.log(calendar) // 'japanese'
console.log(locale) // 'ja-JP-u-ca-japanese'

Understanding Intl.DateTimeFormat.prototype.resolvedOptions

The Intl.DateTimeFormat.prototype.resolvedOptions method in JavaScript returns a new object with properties reflecting the locale and date/time formatting options computed during initialization. It belongs to the Intl.DateTimeFormat object and is one of the most widely used methods for working with intl.datetimeformat values in modern JavaScript and TypeScript applications.

The method signature is dateTimeFormat.resolvedOptions(). When called, it returns an object with resolved locale and formatting options. Understanding when and how to use resolvedOptions() helps you write more expressive, readable code.

Common use cases for Intl.DateTimeFormat.prototype.resolvedOptions include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like intl-datetimeformat, intl-datetimeformat-format, intl-numberformat-resolvedoptions, enabling you to chain operations together for complex data manipulation pipelines.

Browser support for Intl.DateTimeFormat.prototype.resolvedOptions 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.

Browser Compatibility

Supported in all modern browsers (Chrome, Firefox, Safari, Edge) and Node.js. Part of the ECMAScript standard.

Related Methods

More Intl.DateTimeFormat Methods

Other methods in the Intl.DateTimeFormat object

Related Tools

More Intl.DateTimeFormat Methods

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