MONTHBYWEEK¶
Category: EGTools-only function
The month a date's week belongs to, by week-start and owner weekday.
Syntax¶
=MONTHBYWEEK(date, [start_of_week], [owner_of_week])
Arguments¶
| Argument | Required | Description |
|---|---|---|
| date | Required | the date |
| start_of_week | Optional | week start day 1=Sun…7=Sat (default 2=Mon) |
| owner_of_week | Optional | owner day deciding the month (default 5=Thu) |
Returns¶
Returns the month (1-12, scalar number) the date's week belongs to. An unparseable date or a weekday argument outside 1-7 returns a #VALUE! error.
Examples¶
| Formula | Result | Description |
|---|---|---|
=MONTHBYWEEK(DATE(2026,2,1)) |
1 | Sun Feb 1's week belongs to January |
=MONTHBYWEEK(DATE(2026,2,2)) |
2 | Feb 2's week belongs to February |
Notes¶
- Weekday numbers are 1=Sun to 7=Sat; defaults are Monday start and Thursday owner.
- A week's month is the month containing its owner weekday.
- If the date is an array, the function is applied element-wise and spills an array of the same shape (an error element returns that error).
- Related function: WEEKNUMOFMONTH
- Supported: Excel 2010+. Always registered as
MONTHBYWEEKon every Excel version.