How to find the weekday for any date

Welcome to the site! Here, you’ll learn how to calculate the day of the week for any date between 1900 and 2099. We break the calculation down into manageable steps, making it easy and fast. Want to try it out? Use the "Find a Day" tool—just input any date from 1900 to 2099 and follow the steps to find out what day it lands on. If you’re up for a challenge, don’t miss the 5-minute test to see how quickly you can determine the weekdays for random dates!

Why Should I Care? 🤔

Imagine you could figure out the exact day of the week for any date in seconds—without Google! Here are some ways you might use it:

Ready to give it a try? Let’s dive in and start calculating those weekdays!


How to Find the Day of the Week

The process relies on using "anchor dates" in each month. By following a set of simple calculations, you can find out what day of the week a specific date falls on.


1. Find the "anchor date" for the month:
  • January: 1/3 (1/4 in leap years)
  • February: 2/28 (2/29 in leap years)
  • March: 3/14 (pi day, 3.14)
  • April: 4/4
  • May: 5/9
  • June: 6/6
  • July: 7/11 (gas station)
  • August: 8/8
  • September: 9/5 (Dolly Parton)
  • October: 10/10
  • November: 11/7
  • December: 12/12

Example: December 2nd, 1965
  • Anchor Date: For December, the "anchor date" is 12/12.

These "anchor dates" will always be the same day of the week as each other, regardless of the year.

How to determine if it's a leap year.

  1. Leap Years are any year that can be exactly divided by 4 (such as 1904, 1908, 2020, 2024, etc)
  2. except if it can be exactly divided by 100, then it isn't a leap year (such as 1900)
  3. unless it can be exactly divided by 400, then it IS a leap year (such as 2000)

2. Calculate the difference in days from the selected date.
  • Find the number of days between the selected date and the anchor date for that month. Then take this difference and divide it by 7, keeping the remainder. This remainder will tell you how many weekdays forward (or backward) from the anchor date the actual date is.
Example: December 2nd, 1965
  • Difference from anchor date: For December, the "anchor date" is 12/12. 12/2 (the selected date) is -10 from the anchor date (2-12=-10). Reduce this by dividing by 7 and finding the remainder, and you will get -3.

3. Find the century modifier.
  • For the 1900s, the century modifier is 3.
  • For the 2000s, the century modifier is 2.
Example: December 2nd, 1965
  • Century Modifier: 1965 is in the 1900's, and therefore the Century Modifier is 3.

4. Find the Year calculations
  1. Take the last two digits of the year (e.g. 1965 becomes 65).
  2. Quotient: Divide this number by 12. The result is called the quotient. (e.g. 65/12 = 5)
  3. Remainder: Calculate the remainder of this division (the amount left over after dividing by 12). (e.g. 65%12=5)
  4. (Remainder ÷ 4): Divide the remainder by 4. (e.g. 5%4=1)
Example: December 2nd, 1965
  1. Last 2 digits of 1965 becomes 65.
  2. Quotient: 65/12 = 5
  3. Remainder: 65%12=5
  4. (Remainder ÷ 4): 5%4=1

5. Add it all together and find the day
  1. Add together the following: Anchor Date Difference + Century Modifier + Quotient + Remainder + (Remainder ÷ 4)
  2. Find the remainder after dividing the result by 7
  3. Look at the below to determine the day of the week:
    • 0 = Sunday
    • 1 = Monday (Oneday)
    • 2 = Tuesday (Twosday)
    • 3 = Wednesday
    • 4 = Thursday
    • 5 = Friday
    • 6 = Saturday
Example: December 2nd, 1965
  1. -3 + 3 + 5 + 5 + 1 = 11
  2. 11 % 7 = 4
  3. 4 = Thursday
December 2nd, 1965 is a Thursday