What is roman date of purim?

Purim is the 14th of Adar. Shushan Purim (Purim celebrated in walled cities from the time of Joshua) is on the 15th day of Adar. This is when Purim is celebrated today in Jerusalem. Note, that depending when these dates fall out with respect to the Shabbat, the observation of the day's mitzvot may be moved up so as not to conflict with the Shabbat.