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isSameDay

Checks if two dates are the same day.

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

Available since v2.0.0

import { isSameDay } from '@helpers4/date';
// or, from the all-in-one package (same code, one install):
import { isSameDay } from 'helpers4/date';
isSameDay(date1: DateLike, date2: DateLike): boolean
ParameterTypeDescription
date1DateLikeFirst date
date2DateLikeSecond date

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

Returns true when both dates are on the same calendar day.

isSameDay(new Date('2025-01-19T08:00:00'), new Date('2025-01-19T22:00:00'))
// => true

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

View source on GitHub