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July 18, 1788 was a
Friday

July 18, 1788 was a Friday — that’s 86,887 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
200 of 366
ISO week
Week 29
Leap year?
Yes
Zodiac sign
Cancer
Days ago
86,887

How to solve: July 18, 1788

  1. 1
    Century anchor1700s→Sunday (0)
    Practice →
  2. 2
    Divide by 1288 ÷ 12→7
    Practice →
  3. 3
    Remainder of 1288 % 12→4
    Practice →
  4. 4
    Divide remainder by 44 ÷ 4→1
    Practice →
  5. 5
    Year's doomsday(0 + 7 + 4 + 1) % 7→5 → Friday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance18 − 11→7
    Practice →
  8. 8
    Final answer(5 + 7) % 7→5 → Friday

On this day in history

  • 1918Birth of Nelson Mandela
  • 1968Intel is founded

Related dates

Day beforeJuly 17, 1788 — ThursdayDay afterJuly 19, 1788 — SaturdayOne year earlierJuly 18, 1787 — WednesdayOne year laterJuly 18, 1789 — 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?