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August 17, 1989 was a
Thursday

August 17, 1989 was a Thursday — that’s 13,445 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
Thursday
Day of year
229 of 365
ISO week
Week 33
Leap year?
No
Zodiac sign
Leo
Days ago
13,445

How to solve: August 17, 1989

  1. 1
    Century anchor1900s→Wednesday (3)
    Practice →
  2. 2
    Divide by 1289 ÷ 12→7
    Practice →
  3. 3
    Remainder of 1289 % 12→5
    Practice →
  4. 4
    Divide remainder by 45 ÷ 4→1
    Practice →
  5. 5
    Year's doomsday(3 + 7 + 5 + 1) % 7→2 → Tuesday
    Practice →
  6. 6
    Month doomsdayAugust→8th
    Practice →
  7. 7
    Distance17 − 8→9
    Practice →
  8. 8
    Final answer(2 + 9) % 7→4 → Thursday

Related dates

Day beforeAugust 16, 1989 — WednesdayDay afterAugust 18, 1989 — FridayOne year earlierAugust 17, 1988 — WednesdayOne year laterAugust 17, 1990 — Friday
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 Thursday' refers to several historical events that occurred on a Thursday, including a major stock market crash in 1929?