In 5 Digit mode select a Date and receive back the 5 Digit Julian Date, i.e. June 29th, 2017, would be 17180. (17) being the year 2017 and (180) being the 180th day in 2017. Purchase the Full Julian Date mode and June 29th, 2017 12:17:54 PM would be 2457934.01243. You also are able to get the Calendar Date from the Julian Date.