Intl.RelativeTimeFormat

The Intl.RelativeTimeFormat object enables language-sensitive relative time formatting.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

Constructor

Intl.RelativeTimeFormat.RelativeTimeFormat()

Creates Intl.RelativeTimeFormat objects.

Properties

Intl.RelativeTimeFormat.prototype

Allows the addition of properties to all objects.

Methods

Intl.RelativeTimeFormat.supportedLocalesOf()

Returns an array containing those of the provided locales that are supported without having to fall back to the runtime's default locale.

RelativeTimeFormat instances

Properties

RelativeTimeFormat instances inherit the following properties from their prototype:

Intl.RelativeTimeFormat.prototype.constructor

A reference to Intl.RelativeTimeFormat.

Methods

RelativeTimeFormat instances inherit the following methods from their prototype:

Intl.RelativeTimeFormat.prototype.format()

Formats a value and a unit according to the locale and formatting options of the given Intl.RelativeTimeFormat object.

Intl.RelativeTimeFormat.prototype.formatToParts()

Returns an Array of objects representing the relative time format in parts that can be used for custom locale-aware formatting.

Intl.RelativeTimeFormat.prototype.resolvedOptions()

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

Examples

Basic format usage

The following example shows how to use a relative time formatter for the English language.

// Create a relative time formatter in your locale
// with default values explicitly passed in.
const rtf = new Intl.RelativeTimeFormat("en", {
    localeMatcher: "best fit", // other values: "lookup"
    numeric: "always", // other values: "auto"
    style: "long", // other values: "short" or "narrow"
});

// Format relative time using negative value (-1).
rtf.format(-1, "day");
// > "1 day ago"

// Format relative time using positive  value (1).
rtf.format(1, "day");
// > "in 1 day"

Using formatToParts

The following example shows how to create a relative time formatter returning formatted parts

const rtf = new Intl.RelativeTimeFormat("en", { numeric: "auto" });

// Format relative time using the day unit.
rtf.formatToParts(-1, "day");
// > [{ type: "literal", value: "yesterday"}]

rtf.formatToParts(100, "day");
// > [{ type: "literal", value: "in " }, 
// >  { type: "integer", value: "100", unit: "day" }, 
// >  { type: "literal", value: " days" }]

Specifications

Browser compatibility

See also

• The Intl.RelativeTimeFormat API