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July 21, 1918 was a
Sunday

July 21, 1918 was a Sunday — that’s 39,404 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
Sunday
Day of year
202 of 365
ISO week
Week 29
Leap year?
No
Zodiac sign
Cancer
Days ago
39,404

How to solve: July 21, 1918

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1218 ÷ 12→1
    Practice →
  3. 3
    Remainder of 1218 % 12→6
    Practice →
  4. 4
    Divide remainder by 46 ÷ 4→1
    Practice →
  5. 5
    Year's doomsday(3 + 1 + 6 + 1) % 7→4 → Thursday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance21 − 11→10
    Practice →
  8. 8
    Final answer(4 + 10) % 7→0 → Sunday

On this day in history

  • 1899Birth of Ernest Hemingway

Related dates

Day beforeJuly 20, 1918 — SaturdayDay afterJuly 22, 1918 — MondayOne year earlierJuly 21, 1917 — SaturdayOne year laterJuly 21, 1919 — Monday
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 Sunday roast is a traditional British meal typically served on Sundays?