Have you ever wondered what day of the week you or your Great-great Grandparents were born on (I was curious, turns out I was born on a Tuesday)? What day of the week some global, historic event took place on or what day Chirstmas falls in the year 3000?
Maybe you're doing a history project and you want to really impress your teacher by giving them the day of the event; perhaps you need to remind yourself what day it was when you proposed...?
Use this simple Day of the Week Calculator below to find out what day of the week a specific date was or will be.
Select a Month, a Day and a Year and hit the button! ππ½
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If you're a Math's or numbers fiend, here's a peek behind the curtain.
In modern web development, we use the built-in JavaScript Date object. However, behind the scenes, computers often use an algorithm called Zeller's Congruence.
Zeller's Congruence is a formula that calculates the day of the week for any Julian or Gregorian calendar date. The "simplified" version of the math looks like this:
The result h gives a value that corresponds to the day (where 0 is Saturday, 1 is Sunday, etc.).
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The seven-day week originated in ancient Babylon and was later adopted by the Romans. Most Western languages name the days after the "seven celestial bodies" visible to the naked eye: the Sun, Moon, Mars, Mercury, Jupiter, Venus, and Saturn.
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