How to Use WEEKDAY in Excel: Simple Guide with Examples

Use the WEEKDAY function in Excel to find the day number of a date, where Sunday is 1 by default. The syntax is WEEKDAY(serial_number, [return_type]), where serial_number is the date and return_type controls which day is counted as 1.

Syntax

The WEEKDAY function has two parts:

• serial_number: The date you want to check. It can be a date cell or a date entered with DATE function.
• return_type (optional): A number that decides which day is counted as 1. If omitted, Sunday is 1.

excel

WEEKDAY(serial_number, [return_type])

Example

This example shows how to find the weekday number for April 27, 2024, with Sunday as 1 and Monday as 1.

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=WEEKDAY(DATE(2024,4,27))
=WEEKDAY(DATE(2024,4,27), 2)

Output

7
6

Common Pitfalls

People often forget the return_type and get unexpected results because the default counts Sunday as 1. Also, entering dates as text can cause errors.

Always use proper date formats or the DATE function to avoid mistakes.

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=WEEKDAY("4/27/2024")  <em>(May cause error if date is text)</em>
=WEEKDAY(DATE(2024,4,27), 2)  <em>(Correct way)</em>

Quick Reference

Return_type	Day 1	Day 7
1 or omitted	Sunday	Saturday
2	Monday	Sunday
3	Monday	Sunday

Key Takeaways

WEEKDAY returns a number for the day of the week from a date.

Use the optional return_type to change which day counts as 1.

Always input dates as proper date values, not text.

Default return_type counts Sunday as 1.

Use return_type 2 to count Monday as 1 for easier workweeks.