Since March 2025, this feature works across the latest devices and browser versions. This feature might not work in older devices or browsers.
The resolvedOptions() method of Intl.DurationFormat instances returns a new object with properties reflecting the options computed during initialization of this DurationFormat object.
resolvedOptions()
None.
A new object with properties reflecting the options computed during the initialization of this DurationFormat object. The object has the following properties, in the order they are listed:
localeThe BCP 47 language tag for the locale actually used, determined by the locale negotiation process. Only the nu Unicode extension key, if requested, may be included in the output.
numberingSystemThe value provided for this property in the options argument, or using the Unicode extension key "nu", with default filled in as needed. It is a supported numbering system for this locale. The default is locale dependent.
styleThe value provided for this property in the options argument, with default filled in as needed. It is either "long", "short", "narrow", or "digital". The default is "short".
years, yearsDisplay, months, monthsDisplay, weeks, weeksDisplay, days, daysDisplay, hours, hoursDisplay, minutes, minutesDisplay, seconds, secondsDisplay, milliseconds, millisecondsDisplay, nanoseconds, nanosecondsDisplayThe values provided for these properties in the options argument, with defaults filled in as needed. For the valid values and defaults for each, see the options argument of the constructor.
fractionalDigits OptionalThe value provided for this property in the options argument. It is only present if specified in options. It is an integer from 0 to 9, inclusive.
const duration = new Intl.DurationFormat("en");
const usedOptions = duration.resolvedOptions();
usedOptions.locale; // "en"
usedOptions.numberingSystem; // "latn"
usedOptions.years; // "long"
usedOptions.yearsDisplay; // "auto"
usedOptions.style; // "long"
| Desktop | Mobile | Server | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | Bun | Deno | Node.js | |
resolvedOptions |
129 | 129 | 136 | 115 | 16.4 | 129 | 136 | 86 | 16.4 | 28.0 | 129 | 16.4 | 1.0.3 | 1.46 | 23.0.0 |
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DurationFormat/resolvedOptions