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July 16, 1909 was a
Friday

July 16, 1909 was a Friday — that’s 42,696 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
Friday
Day of year
197 of 365
ISO week
Week 28
Leap year?
No
Zodiac sign
Cancer
Days ago
42,696

How to solve: July 16, 1909

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 129 ÷ 12→0
    Practice →
  3. 3
    Remainder of 129 % 12→9
    Practice →
  4. 4
    Divide remainder by 49 ÷ 4→2
    Practice →
  5. 5
    Year's doomsday(3 + 0 + 9 + 2) % 7→0 → Sunday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance16 − 11→5
    Practice →
  8. 8
    Final answer(0 + 5) % 7→5 → Friday

On this day in history

  • 1945Trinity test (First detonation of a nuclear weapon)

Related dates

Day beforeJuly 15, 1909 — ThursdayDay afterJuly 17, 1909 — SaturdayOne year earlierJuly 16, 1908 — ThursdayOne year laterJuly 16, 1910 — Saturday
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 'Black Friday' refers to the day after the U.S. Thanksgiving, which marks the beginning of the Christmas shopping season?