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Day of the week calculator

Find out which day of the week any date falls on.

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Need Day of the week? The Day of the week calculator derives it from Date in one step. For instance, with Date = 1985-03-20 it returns Day of the week = wed.

How to use it

  1. Enter your values: Date.
  2. Read the result instantly: Day of the week.

Frequently asked questions

What does the Day of the week calculator actually compute?

It takes Date and derives Day of the week from them. The calculation is live as you type, so the result updates on every change.

What information do I need to provide?

A single value: Date. Nothing else is required — no account, no file upload.

Can you show a worked example?

With Date = 1985-03-20, the calculator returns Day of the week = wed. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

When would I actually use this?

Answering a scheduling question exactly: how many working days until a deadline, what date falls sixty days out, and what time that is for a colleague elsewhere.

What is the most common mistake?

Counting days by subtracting dates and forgetting whether the endpoints are included. Inclusive and exclusive counts differ by one, which is the difference between meeting a deadline and missing it.

What is the difference between the Day of the week calculator and the Birth Day of the Week Calculator?

This one returns Day of the week; the Birth Day of the Week Calculator returns Result. That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Week number calculator is the closest one after this: Find the ISO week number for any date of the year.

What else is worth having open alongside it?

Sick day believability calculator and Snow day calculator — they come up in the same task often enough to be worth a second tab.

Where do the figures come from, and how current are they?

Calendar arithmetic follows the proleptic Gregorian calendar and the IANA time-zone database, so daylight-saving transitions and leap years are handled. Public holidays vary by country and region and are not assumed.

Further reading

All guides →
How-toWhat Day of the Week Was I Born? Find Out in SecondsFind the weekday of any birth date. Learn the quick calculator method and a short introduction to the Doomsday rule for working it out in your head.How-toHow to Convert Time Zones: UTC Offsets, Day Rollover and DSTConverting between time zones is adding or subtracting the difference in UTC offsets, then handling any day rollover. Learn the method, a worked example, and the DST caveat.ExplainerHow Daylight Saving Time Works: Spring Forward, Fall BackDaylight saving time shifts clocks an hour in spring and back in autumn. Learn spring-forward and fall-back, why one day is 23 hours and another 25, and how US and EU dates differ.How-toHow Many Days Have I Been Alive? Count Days, Weeks and MonthsYour age in days is the whole number of days between your birth date and today. Learn how to count it by hand, convert it to weeks and months, and why leap years matter.How-toCountdown to New Year: How to Count the Days and Weeks LeftBuilding a countdown to a target date is just counting whole days from today to the target, then splitting that total into weeks. Learn the method with a worked example.ExplainerWhat Generation Am I? Birth-Year Cutoffs ExplainedBoomer, Gen X, Millennial, Gen Z or Alpha? Learn the commonly used birth-year ranges, why the boundaries are fuzzy, and how to place yourself if you were born near a cutoff.