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How to Find the Day of the Week for Any Date

Calculate What Day of the Week it is With Our Simple Formula

Written By: Catherine Boeckmann Executive Digital Editor and Master Gardener

What day did that happen? It’s easy to find the day of the week for births, weddings, deaths, and other historical events. Follow our simple instructions to calculate the day for any historical or future date—as far back as the mid-1700s.

For example, what day of the week was December 26, 2004, when the tsunami struck the Indian Ocean? Follow the example as you read along:

  1. Take the last two digits of the year.
  2. Add to that one–quarter of those two digits (discard any remainder).

  3. Add to that the day of the month and the Month Key number for that month:

    Read Next
    January = 1June = 5
    …leap year = 0July = 0
    February = 4August = 3
    …leap year = 3September = 6
    March = 4October = 1
    April = 0November = 4
    May = 2December = 6
  4. Divide the sum by 7. The remainder is the day of the week! One is Sunday, two is Monday, and so on. If there is no remainder, the day is Saturday. 
    [Note: At this step, it may be easiest to use long division to get the remainder. When using a calculator, after you divide the sum by 7, you’ll need to multiply the numbers after the decimal (not the whole number) in the result by 7 and then round to the nearest whole number to get the remainder.]

Note: 

  • If you’re searching for a week before 1900, add 2 to the sum before dividing; before 1800, add 4.
  • The formula doesn’t work for days before 1753.
  • From 2000 to 2099, subtract 1 from the sum before dividing.

Here’s an Example:

A tsunami occurred in the Indian Ocean on December 26, 2004.

Last two digits of year04
One-quarter of these two digits1
Given day of month:26
Key number for December6

Sum: 37

Because 2004 is in the range of 2000 to 2099, subtract 1 from 37. This yields 36.

36 divided by 7 = 5, with a remainder of 1. The tsunami took place on Sunday, the first day of the week.

Monday’s child is fair of face, 
Tuesday’s child is full of grace, 
Wednesday’s child is full of woe, 
Thursday’s child has far to go, 
Friday’s child is loving and giving, 
Saturday’s child works hard for a living, 
And the child that is born on the Sabbath Day, 
Is bonny and blithe and good and gay. 
–an old English nursery rhyme

Or… if you want to make it easy, check out our Day of the Week Calculator! It does the work for you!

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About The Author
Catherine Boeckmann

Catherine Boeckmann

Executive Digital Editor and Master Gardener

Catherine Boeckmann is the Executive Digital Editor of Almanac.com, the website companion of The Old Farmer's Almanac. She covers gardening, plants, pest control, soil composition, seasonal and moon c...
Read More from Catherine Boeckmann

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Comments

<span>Vince</span> Thu, 05/02/2024 - 14:24
This did not work in the case of June 18th, 1997 97/4 = 24.25 24 + 97 = 121 121+ 18 = 139 139+ 5 = 144 Since it’s not between 2000-2099 I didn’t subtract. 144/7 20.5 5 = Thursday June 18th 97 was a Wednesday. Any reason this was wrong?
<span>Victor Maratovich</span> Sat, 07/06/2024 - 09:20
144÷7 =20 with a remainder of 4, not 5
<a title="View user profile." href="/author/editors">The Editors</a> Mon, 05/06/2024 - 09:40

Hi, Vince,

For this formula to work, we need to use long division rather than a calculator or similar to determine the remainder. A calculator would say 20.571... is the result of 144 divided by 7, but the "0.5" would not be the remainder. So, in the below long division formula, "4" would be the remainder -- which is Wednesday.

   _ 20
7 | 144
     14 
    —
      04


Hope this helps!     

 

 

 <span>Tom Sheldin</span> Thu, 03/07/2024 - 18:28
Where do the 49 and 54 come from?
<a title="View user profile." href="/author/editors">The Editors</a> Mon, 05/06/2024 - 09:15

Hi, Tom,

Using the long division method, 7 goes into 12 (first two digits of "124") one time. (The number "1" goes up top, over the 2 in "124.") Put "7" under the "12," and subtract. So 12 minus 7 is 5. Then, bring down the "4" in the "124" (the next digit to right) to make "54." Then, 7 goes into "54" seven times. (The number "7" goes up top, over the "4" in 124.) So 7 times 7 is 49. Subtract 49 from 54, and we get 5, the remainder. Hope this helps!

   _17
7 | 124
      7
    —
      54
      49
      —
        5

 <span>Kishan</span> Sun, 01/28/2024 - 19:54
what is the number to be subtracted for other centuries, as you stated for the 21st century it is one but for others?
<span>George</span> Fri, 12/22/2023 - 00:07
The formula does not seem to work for December 25, 1951
<span>George</span> Sat, 12/23/2023 - 10:40
Never mind, I found my mistake and it does wok for that date.
<span>Michael</span> Wed, 02/22/2023 - 19:11
Does anybody “understand why” we subtract 1 for January of a leap year? The extra day does not occur until the end of February !!! This is itching my brain.
<span>Charlie</span> Fri, 05/10/2024 - 13:24
Yes... it's because you already "added" one first when you divided 4 into the year number. For instance if the year was 2020, you divided 20/4 and added a "5"..... But that number 5 isn't correct until after Feb. 29, so until then you need to subtract 1.