Year 304 (CCCIV) was a leap year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Valerius and Valerius (or, less frequently, year 1057 Ab urbe condita). The denomination 304 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

Year 304 (CCCIV) was a leap year starting on Saturday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Valerius and Valerius (or, less frequently, year 1057 Ab urbe condita). The denomination 304 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.