The function WEEEKDAY takes a date or a DateTime and returns a number indicating what day of the week the given date falls on.

This function takes either a single DateTime or a single date as input. It then returns a number indicating what day of the week the given date falls on. Count starts with01 and Sunday (that is, 0 represents Sunday, 1 represents Monday, 2 represents Tuesday, 3 represents Wednesday, et cetera).

### Declaration

``````WEEKDAY(datetime) -> day
``````
``````WEEKDAY(date) -> day
``````

### Parameters

datetime (type: DateTime)
Any DateTime.

date (type: date)
Any date.

### Return Values

day (type: number)
A number (0-6) indicating what day of the week is described by the given date or DateTime.
Count starts with 0 and Sunday (that is, 0 represents Sunday, 1 represents Monday, 2 represents Tuesday, 3 represents Wednesday, et cetera).

### Examples

``````example_date_and_time = {
"date": {
"day": 1,
"month": 4,
"year": 2021
},
"time": {
"hour": 16,
"minute": 14,
"second": 38,
"millisecond": 0
},
"timeZone": "UTC"
}
``````

The date described in example_date_and_time is April 1st, 2021. This falls on a Thursday, which WEEKDAY indexes as 4. Thus, in the following example, when example_date_and_time is given as input for WEEKDAY, it returns the number 4:

``````WEEKDAY(example_date_and_time) = 4
``````

The above example demonstrates how the WEEKDAY function behaves when given a DateTime as input. In order to further establish how the WEEKDAY function behaves when given a date as input, assume the last example has access to the following date value:

``````example_date = {
"day": 1,
"month": 4,
"year": 2021
}
``````

Note that the date described in example_date is identical to the date described in example_date_and_time. This is still a Thursday, when example_date is given as input for WEEKDAY, it returns the number 4:

``````WEEKDAY(example_date) = 4
``````