Intl.NumberFormat

Intl.NumberFormat.prototype.resolvedOptions

Returns a new object with properties reflecting the locale and number formatting options computed during initialization

Syntax

JavaScript
numberFormat.resolvedOptions()

Return Value

An object with resolved locale and formatting options

Examples

Basic Usage
const fmt = new Intl.NumberFormat('en-US', { style: 'currency', currency: 'USD' })
const opts = fmt.resolvedOptions()
console.log(opts.locale) // 'en-US'
console.log(opts.currency) // 'USD'
Practical Example
const fmt = new Intl.NumberFormat('de')
const { numberingSystem, locale } = fmt.resolvedOptions()
console.log(numberingSystem) // 'latn'
console.log(locale) // 'de'
Advanced Usage
function getDecimalSeparator(locale: string): string {
  const fmt = new Intl.NumberFormat(locale)
  const parts = fmt.formatToParts(1.1)
  return parts.find(p => p.type === 'decimal')?.value || '.'
}

Understanding Intl.NumberFormat.prototype.resolvedOptions

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

The method signature is numberFormat.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.NumberFormat.prototype.resolvedOptions include data transformation, input validation, API response processing, and building reusable utility functions. It works well alongside related methods like intl-numberformat, intl-numberformat-format, intl-datetimeformat, enabling you to chain operations together for complex data manipulation pipelines.

Browser support for Intl.NumberFormat.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.NumberFormat Methods

Other methods in the Intl.NumberFormat object

Related Tools

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