How to Calculate in Your Head the Year when You Know the Month, Day and Day of the Week

Step-by-Step Guide

1. 1

   Step 1: Select some Start Year by any method you have available

   (Do not worry if you turn out to be wrong because you will be able to make up for this later in step
   5.) Using the method explained in another LifeGuide Hub article of mine (see first link), compute the Day of the Week for the Month and Day that have for the Target Year, but in this case for the Start Year.
2. 2

   Step 2: trying to make it no more than 5 years BEFORE the Target Year that you are looking for.

   If that value is less than the value (from step 1) for the Day of the Week in the Start Year, add 7 to it.
   
   Now subtract the value for the Day of the Week for the Start Year (from step 1) from the value for the Day of the Week for the Target Year that you just looked up and perhaps adjusted.
   
   Let's call this result the Day of the Week (DOW) Gap. , Let's call this the Leap Gap.
   
   If the month is January of February, add 1 to the Leap Gap, but if this makes the result 5, then change it to 1 (this will happen when the Start Date is in January or February in an actual leap year). , But add 5 to this if the DOW Gap is equal to the Leap Gap or subtract 1 from it if the DOW Gap is greater than Leap Gap (but if the Dow Gap is 6 and the Leap Gap is 1, do both, that is, add 4).
   
   This is the first occurrence of the Target Year after the Start Year.
   
   If this turns out to be the actual Target Year you are looking for, your task is done. , Now, go to the table to the right and find that Leap Gap (numbers 1-4) among the numbers in red outside the circle.
   
   To find the occurrences of the Target Year PRIOR to the first one you found in step 4, move counter-clockwise from the point at which you entered the circle, subtracting the indicated numbers (inside the circle) from the last Target Year to jump to the next prior Target Year.
   
   To jump to the NEXT occurrences of the Target Year AFTER the first one you found in step 4, move clockwise from the point at which you entered the circle, adding the indicated numbers (inside the circle) to the last Target Year to jump to the next subsequent Target Year. (This is why we call those numbers in the circle the Jump numbers.) You can keep going round and round the circle as long as like as long you stay within a century (see tips).
3. 3

   Step 3: Look up the value for Day of the Week that you have for the Target Year in the above table.

4. 4

   Step 4: Compute the number of years from the Start Year to the next Leap Year.

5. 5

   Step 5: To find the first occurrence of your Target Year after the Start Year

6. 6

   Step 6: add the DOW Gap (from step 2) to the Start Year that you chose for step 1.

7. 7

   Step 7: In the event that you overshot or undershot the Start Year and

8. 8

   Step 8: missed the actual Target Year

9. 9

   Step 9: you can make adjustments quickly by computing the prior or next yearly occurrences of the Target Date as follows: Compute the Leap Gap from the Target Year to the next Leap Year exactly as you did in step 3

10. 10

    Step 10: above.

Detailed Guide

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