Tags: #instructions # Determining the Day of the Week for Any Date **This method only works for the year 1753 or after.** ## Memorize This Table | <!-- --> | <!-- --> | | --------- | -------- | | January | 1 | | February | 4 | | March | 4 | | April | 0 | | May | 2 | | June | 5 | | July | 0 | | August | 3 | | September | 6 | | October | 1 | | November | 4 | | December | 6 | Some additional ways of putting it: - 1, 4, 4, 0, 2, 5, 0, 3, 6, 1, 4, 6. - 144, 025, 036, 146 - Gross, quarter, 36, 1-46 ## Use This Formula ``` (YD+floor(YD/4)+C+(MC+L)+D) % 7 ``` - ⁠YD = Year Digits - the last two digits of the Year. - ⁠C = Century Modifier - 1753-1799 = +4 - ⁠1800-1899 = +2 - ⁠1900-1999 = 0 - ⁠2000-2099 = -1 - ⁠MC = the number code for the month (memorized above) - L = Leap Modifier - 0, or -1 if Jan/Feb and year is divisible by 4 - ⁠D = the day of the month ## Map Result to Day | <!-- --> | <!-- --> | | --------- | -------- | | Saturday | 0 | | Sunday | 1 | | Monday | 2 | | Tuesday | 3 | | Wednesday | 4 | | Thursday | 5 | | Friday | 6 |