Hồ Ngọc Đức Lunar Calendar (Am lich) running in Nodejs
Go to the link bellow for more detail http://www.informatik.uni-leipzig.de/~duc/amlich/
Calculate Julian day number (the number of days between 1/1/4713 BC (Julian calendar) and dd/mm/yyyy)
Convert a Julian day number to day/month/year
Convert a lunar date to the corresponding solar date
Convert solar date dd/mm/yyyy to the corresponding lunar date