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July 31, 2015 was a
Friday

July 31, 2015 was a Friday — that’s 3,965 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
212 of 365
ISO week
Week 31
Leap year?
No
Zodiac sign
Leo
Days ago
3,965

How to solve: July 31, 2015

  1. 1
    Century anchor2000s→Tuesday (2)
    Practice →
  2. 2
    Divide by 1215 ÷ 12→1
    Practice →
  3. 3
    Remainder of 1215 % 12→3
    Practice →
  4. 4
    Divide remainder by 43 ÷ 4→0
    Practice →
  5. 5
    Year's doomsday(2 + 1 + 3 + 0) % 7→6 → Saturday
    Practice →
  6. 6
    Month doomsdayJuly→11th
    Practice →
  7. 7
    Distance31 − 11→20
    Practice →
  8. 8
    Final answer(6 + 20) % 7→5 → Friday

Related dates

Day beforeJuly 30, 2015 — ThursdayDay afterAugust 1, 2015 — SaturdayOne year earlierJuly 31, 2014 — ThursdayOne year laterJuly 31, 2016 — 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 Friday is often the day for high-profile music and film releases?