Day of the week calculator
Answers to Questions
How to calculate the day of the week?
Calculation needs a date (day, month, year) in the Gregorian Calendar (or Julian before 1582) and some mathematics formula.
There are algorithms that allow a mental calculation (not necessarily easy), but they become false for dates before 1900.
Example: The first january 2000 was a Saturday.
Overall, it is highly probable that before 1900 the days of the week were not perfectly managed in all regions. The Gregorian calendar was not as widespread in Europe, and globally, the values proposed by dCode before 1900 are mathematically correct, but may have shifts with the practices of the time that were not rigorous...
What is the difference between the Julian Calendar and the Gregorian Calendar?
There are two differences, the first difference is about the calculus of leap years and the second one, which is a consequence, the Gregorian Calendar had a jump of several days in 1582.
In France, the day after December 9, 1582, was December 20, 1582.
In Europe, the day after Thursday 4 October was Friday 15 October 1582 (this version is used on dCode).
How do historians handle calendar differences?
When there may be confusion or uncertainty about the calendar used, historians specify the location and name of the calendar used.
Example: January 1st of the Gregorian Calendar