Julian Day and Civil Date Calculator

is a
 whose Julian Day Number is 
Calendar: Auto (Julian/Gregorian) Julian Only
(Edit the following field for interval calculations.)
is followed days later by
is a
 whose Julian Day Number is 
Calendar: Auto (Julian/Gregorian) Julian Only
  1. You must have JavaScript enabled in your browser for this calculator to work. Requires Netscape 3.0 or Internet Explorer 3.0 or later for correct operation.
  2. All fields are editable. Change civil date to calculate Julian Day Number and day-of-week, or vice versa.
  3. After changing a text box, click outside of the calculator, or press tab, to update all other data. (Don't press return.)
  4. In Auto mode, civil calendar changes from Julian to Gregorian between October 4/15, 1582. For Julian civil dates after that date, as in England and colonies until 1753, select Julian Only.

Copyright (C) 1998 by Numerical Recipes Software. Permission is granted for unlimited copying and redistribution, provided that this copyright notice, and the following two links, are preserved. All calculations are embedded as JavaScript, so an exact copy of this page's source code will generally work from any server (no CGI script needed).

(You might be interested in NOAA's Sunrise/Sunset Calculator, also a pure JavaScript HTML file with many embedded calendar functions.)

back to Numerical Recipes News
back to Numerical Recipes home page