Day of the Week Calculator

(from https://core2.gsfc.nasa.gov/time/julian.html)

If changing the year, after change, click outside the year box to update the Day of Week.

The last day of the Julian calendar, 2 Sep 1752, is followed by the first day of the Gregorian calendar (currently used calendar), 14 Sep 1752.
The dates 3 Sep 1752 through 13 Sep 1752 inclusive did not exist and are invalid entries.

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