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July 4, 1980 was a
Friday

July 4, 1980 was a Friday — that’s 16,775 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
186 of 366
ISO week
Week 27
Leap year?
Yes
Zodiac sign
Cancer
Days ago
16,775

How to solve: July 4, 1980

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1280 ÷ 12→6
    Practice →
  3. 3
    Remainder of 1280 % 12→8
    Practice →
  4. 4
    Divide remainder by 48 ÷ 4→2
    Practice →
  5. 5
    Year's doomsday(3 + 6 + 8 + 2) % 7→5 → Friday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance4 − 11→-7
    Practice →
  8. 8
    Final answer(5 + -7) % 7→5 → Friday

On this day in history

  • 2012CERN announces discovery of the Higgs boson

Related dates

Day beforeJuly 3, 1980 — ThursdayDay afterJuly 5, 1980 — SaturdayOne year earlierJuly 4, 1979 — WednesdayOne year laterJuly 4, 1981 — 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?