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August 21, 1939 was a
Monday

August 21, 1939 was a Monday — that’s 31,704 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
233 of 365
ISO week
Week 34
Leap year?
No
Zodiac sign
Leo
Days ago
31,704

How to solve: August 21, 1939

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1239 ÷ 12→3
    Practice →
  3. 3
    Remainder of 1239 % 12→3
    Practice →
  4. 4
    Divide remainder by 43 ÷ 4→0
    Practice →
  5. 5
    Year's doomsday(3 + 3 + 3 + 0) % 7→2 → Tuesday
    Practice →
  6. 6
    Month doomsdayAugust→8th
    Practice →
  7. 7
    Distance21 − 8→13
    Practice →
  8. 8
    Final answer(2 + 13) % 7→1 → Monday

Related dates

Day beforeAugust 20, 1939 — SundayDay afterAugust 22, 1939 — TuesdayOne year earlierAugust 21, 1938 — SundayOne year laterAugust 21, 1940 — Wednesday
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 Monday is considered the best day to buy a new car, according to some consumer reports?