isSameMonth

Checks if two dates are in the same month (and year).

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

Available since v2.0.0

Import

import { isSameMonth } from '@helpers4/date';
// or, from the all-in-one package (same code, one install):
import { isSameMonth } from 'helpers4/date';

Signature

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

Parameters

Parameter	Type	Description
date1	DateLike	First date
date2	DateLike	Second date

Returns

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

Examples

isSameMonth

isSameMonth('2025-01-01', '2025-01-31') // => true
isSameMonth('2025-01-31', '2025-02-01') // => false

Related Types

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

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

Source

View source on GitHub