Friday January 21, 1555
A date scroll with Latin text from “The Extremes of Good and Evil” by Cicero, written in 45 BC.

January 21, 1555: Day of the Week

January 21, 1555 was the 21st day of the year 1555 in the Gregorian calendar. There were 344 days remaining until the end of the year. The day of the week was Friday.

The day of the week for January 21, 1555 under the old Julian calendar was Monday. Did you notice the difference with the Gregorian calendar?

If you are trying to learn Spanish then this day of the week in Spanish is viernes.

A person born on this day will be 470 years old today. If that same person saved a Nickel every day starting at age 3, then by now that person has accumulated $8,528.65 today.

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Here’s the January 1555 Gregorian calendar. You can also browse the full year monthly 1555 calendar.

January 1555
SunMonTueWedThuFriSat
      1
2345678
9101112131415
16171819202122
23242526272829
3031     

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Zodiac & Birthstone

Aquarius 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 21, 1555 by the Numbers

  • 171,669 days since January 21, 1555
  • 470 years, 0 month, and 4 days ago
  • 5,640 months since then
  • January 21 is in the 3rd week of the year 1555 (ISO 8601)
  • 24,524 weeks ago
  • The year 1555 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 21, 1555). 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.