isSameYear

Checks if two dates are in the same year.

Accepts any DateLike input (Date, timestamp, or date string).

Available since v2.0.0

Import

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

isSameYear(date1: DateLike, date2: DateLike): boolean

Parameter	Type	Description
`date1`	`DateLike`	First date
`date2`	`DateLike`	Second date

boolean — True if same year, false otherwise (including when either date is invalid)

isSameYear('2025-01-01', '2025-12-31') // => true
isSameYear('2024-12-31', '2025-01-01') // => false

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)
Temporal.Instant | Temporal.ZonedDateTime — read via their epochMilliseconds property

type DateLike = Date | number | string | Temporal.Instant | Temporal.ZonedDateTime