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July 15, 1940 was a
Monday

July 15, 1940 was a Monday — that’s 31,374 days ago. Below you can see exactly how to work the weekday out in your head with the Doomsday algorithm, along with a few other facts about the date.

Weekday
Monday
Day of year
197 of 366
ISO week
Week 29
Leap year?
Yes
Zodiac sign
Cancer
Days ago
31,374

How to solve: July 15, 1940

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1240 ÷ 12→3
    Practice →
  3. 3
    Remainder of 1240 % 12→4
    Practice →
  4. 4
    Divide remainder by 44 ÷ 4→1
    Practice →
  5. 5
    Year's doomsday(3 + 3 + 4 + 1) % 7→4 → Thursday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance15 − 11→4
    Practice →
  8. 8
    Final answer(4 + 4) % 7→1 → Monday

Related dates

Day beforeJuly 14, 1940 — SundayDay afterJuly 16, 1940 — TuesdayOne year earlierJuly 15, 1939 — SaturdayOne year laterJuly 15, 1941 — Tuesday
Want to be able to do this for any date in seconds? Read the guide or practice the algorithm.
Did you know? Did you know that in many cultures, Monday is traditionally seen as the start of the dieting week?