timeAgo

Formats a date as a human-readable relative time string.

Uses Intl.RelativeTimeFormat under the hood, making the output locale-aware (e.g. “il y a 3 jours” in French).

Returns null if the input date is invalid.

Available since v2.0.0

Import

import { timeAgo } from '@helpers4/date';

Signature

timeAgo(date: DateLike, options: TimeAgoOptions): string | null

Parameters

Parameter	Type	Description
date	DateLike	The date to describe relative to now
options	TimeAgoOptions	Optional configuration (reference date, locale, numeric style)

Returns

string | null — A locale-aware relative time string, or null

Examples

timeAgo

timeAgo('2025-01-17T00:00:00Z', { now: '2025-01-19T00:00:00Z' })
// => "2 days ago"

timeAgo('2025-01-20T00:00:00Z', { now: '2025-01-19T00:00:00Z' })
// => "in 1 day"  (or "tomorrow" with numeric: 'auto')

timeAgo('2025-01-19T00:00:00Z', { now: '2025-01-19T00:00:05Z' })
// => "5 seconds ago"

Related Types

TimeAgoOptions

Options for timeAgo.

interface TimeAgoOptions {
  locale?: string;
  now?: DateLike;
  numeric?: "always" | "auto";
}

DateLike

A value that can be converted to a Date.

• Date — used as-is (validated for Invalid Date)
• number — treated as a timestamp (seconds or milliseconds, auto-detected); 0 is treated as invalid and produces null in ensureDate
• string — parsed via new Date(string)
• EpochMilliseconds — any object with a epochMilliseconds property (e.g. Temporal.Instant, Temporal.ZonedDateTime)

// TODO: When the Temporal API reaches Stage 4 and is available without // flags in all major runtimes, consider narrowing the union to the // concrete Temporal types for stricter type-checking.

type DateLike = Date | number | string | EpochMilliseconds

EpochMilliseconds

An object that exposes an epoch timestamp in milliseconds.

This structural type is satisfied by Temporal.Instant and Temporal.ZonedDateTime (and any future object that carries the same property), so callers can pass Temporal values without importing them.

interface EpochMilliseconds {
  epochMilliseconds: number;
}

Source

View source on GitHub