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July 10, 1987 was a
Friday

July 10, 1987 was a Friday — that’s 14,213 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
191 of 365
ISO week
Week 28
Leap year?
No
Zodiac sign
Cancer
Days ago
14,213

How to solve: July 10, 1987

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1287 ÷ 12→7
    Practice →
  3. 3
    Remainder of 1287 % 12→3
    Practice →
  4. 4
    Divide remainder by 43 ÷ 4→0
    Practice →
  5. 5
    Year's doomsday(3 + 7 + 3 + 0) % 7→6 → Saturday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance10 − 11→-1
    Practice →
  8. 8
    Final answer(6 + -1) % 7→5 → Friday

Related dates

Day beforeJuly 9, 1987 — ThursdayDay afterJuly 11, 1987 — SaturdayOne year earlierJuly 10, 1986 — ThursdayOne year laterJuly 10, 1988 — Sunday
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?