Skip to content

WEEKDAY Function

The WEEKDAY function in Excel determines the day of the week for a given date, returning a numeric value corresponding to the day. It is highly useful for date analysis, scheduling, and applying conditional logic based on the day of the week.

Syntax

WEEKDAY(date, [return_type])
  • date: The date value for which you want to find the day of the week. This can be:
  • A date serial number.
  • A date string.
  • A result of other date functions like DATE.
  • return_type: (Optional) A numeric argument that determines the numbering system for the days of the week. Values range from 1 to 17.

Returns

The WEEKDAY function returns an integer representing the day of the week for the given date. The numbering system depends on the specified return_type.

return_type Options and Behavior

Return Type Weekday Numbering Description
1 (Default) Sunday = 1, Monday = 2, ..., Saturday = 7 Default behavior in Excel.
2 Monday = 1, Tuesday = 2, ..., Sunday = 7 Commonly used in ISO week conventions.
3 Monday = 0, Tuesday = 1, ..., Sunday = 6 Used in programming and zero-based systems.
11 Monday = 1, Tuesday = 2, ..., Sunday = 7 Same as 2.
12 Tuesday = 1, Wednesday = 2, ..., Monday = 7 Weeks start on Tuesday.
13 Wednesday = 1, Thursday = 2, ..., Tuesday = 7 Weeks start on Wednesday.
14 Thursday = 1, Friday = 2, ..., Wednesday = 7 Weeks start on Thursday.
15 Friday = 1, Saturday = 2, ..., Thursday = 7 Weeks start on Friday.
16 Saturday = 1, Sunday = 2, ..., Friday = 7 Weeks start on Saturday.
17 Sunday = 1, Monday = 2, ..., Saturday = 7 Same as 1.

Examples

Example 1: Basic Usage

Suppose you want to find the day of the week for October 25, 2023:

=WEEKDAY(DATE(2023, 10, 25))

This formula calculates the weekday and returns 4 (Wednesday) using the default return_type (1).

Example 2: Custom Week Start (Monday)

To use Monday as the start of the week:

=WEEKDAY(DATE(2023, 10, 25), 2)

This formula returns 3 (Wednesday) when Monday is 1.

Example 3: Week Start on Friday

To use Friday as the start of the week:

=WEEKDAY(DATE(2023, 10, 25), 15)

This formula returns 6 (Wednesday) when Friday is 1.

Key Features

  1. Flexible Day Numbering: Supports multiple numbering conventions for international or cultural preferences.
  2. Customizable Week Start: Allows selection of any day as the starting point of the week.
  3. Compatible with Other Functions: Useful for conditional operations, trend analysis, and scheduling when combined with functions like IF, CHOOSE, or TEXT.

Notes

  • If return_type is omitted, it defaults to 1 (Sunday = 1, Saturday = 7).
  • Ensure the date is a valid Excel date; otherwise, the function will return a #VALUE! error.
  • return_type values not listed above will result in a #VALUE! error.

The WEEKDAY function in Excel is a robust tool for analyzing date-related data, offering unparalleled flexibility in numbering systems and starting days of the week. Use it to tailor date analyses to meet your specific needs.