Thursday January 1, 1581
A date scroll with Latin text from “The Extremes of Good and Evil” by Cicero, written in 45 BC.

January 1, 1581: Day of the Week

January 1, 1581 was the 1st day of the year 1581 in the Gregorian calendar. There were 364 days remaining until the end of the year. The day of the week was Thursday.

The day of the week for January 1, 1581 under the old Julian calendar was Sunday. Did you notice the difference with the Gregorian calendar?

If you are trying to learn Japanese then this day of the week in Japanese is Mokuyōbi.

A person born on this day will be 443 years old today. If that same person saved a Dime every day starting at age 3, then by now that person has accumulated $16,104.50 today.

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Here’s the January 1581 Gregorian calendar. You can also browse the full year monthly 1581 calendar.

January 1581
SunMonTueWedThuFriSat
    123
45678910
11121314151617
18192021222324
25262728293031

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Zodiac & Birthstone

Capricorn is the zodiac sign of a person born on this day. Garnet is the modern birthstone for this month. Emerald is the mystical birthstone from Tibetan origin that dates back over a thousand years.

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January 1, 1581 by the Numbers

  • 162,140 days since January 1, 1581
  • 443 years, 11 months, and 3 days ago
  • 5,327 months since then
  • January 1 is in the 1st week of the year 1581 (ISO 8601)
  • 23,162 weeks ago
  • The year 1581 is not a leap year

Gregorian versus the old Julian calendar

A note to students, teachers, scholars and anyone else passionate about this topic. As stated in the front page, this website is using the Gregorian calendar as the basis for all “day of the week” computation whether or not the Gregorian calendar is relevant for the date in question (January 1, 1581). Educators should point out the primary reason why Pope Gregory XIII introduced a new calendar system in October 1582. That is, to make the computation for the annual date of Easter more accurate since it is the foundation of the Christian faith.

Even with that purpose in mind, the Gregorian calendar too will become out of sync. It has a known approximation error of about one day for every 7,700 years assuming a constant time interval between vernal equinoxes (which is not true). This is better compared to the one day for every 128 years error of the Julian calendar.

Share InfoNow try another date like anniversaries, birthdays of someone you know or any other date that is special to you. Don’t forget to share the info to your friends, loved ones or social media followers. Who knows, they might appreciate and thank you for it.