Can it handle historical dates?

Yes. Any Gregorian calendar date works, making it great for historical research or future planning.

What if my weekend is Friday/Saturday?

This version flags Saturday/Sunday. For alternate workweeks, interpret the day name accordingly.

Which day is index 0?

Index 0 is Sunday, 1 is Monday, through 6 for Saturday (JavaScript’s getDay convention).

Does daylight saving time affect the result?

No. Weekday is based on the calendar date, not the clock change.

Does time zone matter?

The day is determined using local time. If coordination across time zones is critical, standardize to UTC before calculating.

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Day of Week Calculator

Enter any date to instantly see whether it lands on Monday, Saturday, or another day of the week.

Results

Day index (0=Sun): 5
Day name: Friday
Weekend? (1=yes): 0

How to use this calculator

Enter a date (year, month, day).
The calculator determines the weekday name and index (0–6).
See a weekend flag so you know if it’s Saturday/Sunday.

Inputs explained

Year: Calendar year for the date you’re checking.
Month: Month number (1–12).
Day: Day of month (1–31).

How it works

We run the date through JavaScript’s native weekday function and map the numeric output to a plain-language day name.

A weekend flag highlights Saturdays and Sundays for quick planning.

Formula

Weekday = Date(year, month, day).getDay()

When to use it

Scheduling meetings and checking if they fall on a weekday or weekend.
Verifying historical dates for events, birthdays, or observances.
Coordinating with teams across time zones by standardizing weekday names.

Tips & cautions

Pair this with the Add/Subtract Days tools to shift dates, then confirm the weekday.
Results use local time. For cross-time-zone planning, align on UTC first.
Use the weekend flag to quickly see if a deadline lands on Saturday/Sunday.
No holiday awareness—only weekday vs. weekend.
Weekend definition is Saturday/Sunday; regions with different weekends aren’t configurable.
Assumes Gregorian calendar dates.

Worked examples

July 4, 2025

Falls on a Friday (not a weekend).

January 1, 2028

Lands on a Saturday, so the weekend flag is 1.

Deep dive

This day-of-week calculator shows the weekday name and whether a date is on the weekend. Enter a date to see its weekday index (0–6), name, and a weekend flag instantly.

Use it for scheduling, historical checks, or coordinating with teams across time zones. It uses the Gregorian calendar and a Saturday/Sunday weekend definition.

FAQs

Can it handle historical dates?: Yes. Any Gregorian calendar date works, making it great for historical research or future planning.
What if my weekend is Friday/Saturday?: This version flags Saturday/Sunday. For alternate workweeks, interpret the day name accordingly.
Which day is index 0?: Index 0 is Sunday, 1 is Monday, through 6 for Saturday (JavaScript’s getDay convention).
Does daylight saving time affect the result?: No. Weekday is based on the calendar date, not the clock change.
Does time zone matter?: The day is determined using local time. If coordination across time zones is critical, standardize to UTC before calculating.

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Results are based on the Gregorian calendar with Saturday/Sunday weekends; holidays are not considered.