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July 21, 1964 was a
Tuesday

July 21, 1964 was a Tuesday — that’s 22,602 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
Tuesday
Day of year
203 of 366
ISO week
Week 30
Leap year?
Yes
Zodiac sign
Cancer
Days ago
22,602

How to solve: July 21, 1964

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1264 ÷ 12→5
    Practice →
  3. 3
    Remainder of 1264 % 12→4
    Practice →
  4. 4
    Divide remainder by 44 ÷ 4→1
    Practice →
  5. 5
    Year's doomsday(3 + 5 + 4 + 1) % 7→6 → Saturday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance21 − 11→10
    Practice →
  8. 8
    Final answer(6 + 10) % 7→2 → Tuesday

On this day in history

  • 1899Birth of Ernest Hemingway

Related dates

Day beforeJuly 20, 1964 — MondayDay afterJuly 22, 1964 — WednesdayOne year earlierJuly 21, 1963 — SundayOne year laterJuly 21, 1965 — 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 in Spanish-speaking countries, Tuesday the 13th (and not Friday) is considered an unlucky day?