Instructions 
Example: November 12, 2070 
Step 1: Determine the code for the century:
Century:  1800's  1900's  2000's  2100's 
Code #  2  0  6  4 

Century = 2000's
The code for 2000's is 6
Shortcut: Use 1 instead of 6 for 2000's to make the arithmetic easier.
Total = 6
Flashcards

Step 2: Determine the code for the year:
Year:  00  04  08  12  16  20  24 
28  32  36  40  44  48  52 
56  60  64  68  72  76  80 
84  88  92  96  
Code #  1  6  4  2  0  5  3 

Year = 70
68 is 2, so 69 is 3 and 70 is 4!
Total = 10 (6 + 4)
Flashcards

Step 3: Determine month code:
Jan = 6  Feb = 2  Mar = 2  Apr = 5 
May = 0  Jun = 3  Jul = 5  Aug = 1 
Sep = 4  Oct = 6  Nov = 2  Dec = 4 

Month = November
November = 2
Total = 12 (6 + 4 + 2)
Flashcards

Step 4: Determine date code:
Date:   1  2  3  4  5  6 
7  8  9  10  11  12  13 
14  15  16  17  18  19  20 
21  22  23  24  25  26  27 
28  29  30  31  
Code #  0  1  2  3  4  5  6 

Date = 12
The code for date:12 is 5.
Total = 17(6 + 4 + 2 + 5)
Shortcut #1: Subtract 7, 14, 21 or 28, from the date to find code, dates less than 7 are
already equal to the code.
Example: Nov 12: 12  7 = 5.
Example: Nov 26: 26  21 = 5
Shortcut #2: Simply add the date to the total. Example: Nov 12: Code=12, Total = 24 (6 + 4 + 2 + 12).
Flashcards

Step 5: Determine dayofweek from total
Divide the total from Step 3 by seven, the remainder
giving the dayofweek:
Dayofweek:  Sun  Mon  Tue  Wed  Thu  Fri  Sat 
Remainder:  0  1  2  3  4  5  6 

Total = 17 (Century=6, Year=4, Month=2, Date=5)
17 divided by 7 is: 2 remainder 3
3 = Wednesday
Shortcut: Instead of dividing, just subtract 7, 14, 21, 28, or 35, etc. (multiples of 7)
until you have a number 0 to 6. For example, 17  14 = 3. If the total was 30, then 30  28 = 2 = Tuesday.
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Step 6: Don't forget leapyear!
Subtract 1 at any point in the process only if the year
is a leap year, and the month is January or February!

2070 is not a leap year.
Shortcut #1: The year is a leap year if it is found in the table in step 1. (68 and 72 are leap years, but 70 is not)
Shortcut #2: A year is a leap year if it is evenly divisible by 4.
Shortcut #3: As a last step, you can simply take the day before (if the year is a leap year, and the month is Jan. or Feb.)
Click here
for the rare exceptions to the above shortcuts.
Flashcards
