2004 CE
- Common Era
- 2004 CE
- Gregorian Calendar
- 2004 AD
- Holocene Calendar
- 12004 HE
- Japanese Calendar
- Heisei 16 (平成16年)
- Japanese Imperial Year
- Kōki 2664 (皇紀2664年)
- Chinese Sexagenary Cycle
- Yang Wood Monkey (甲申)
Milestones
- First human in space
- 43 years ago
- World War II ends
- 59 years ago
- Hindu-Arabic numerals introduced to Europe
- 802 years ago
- Mythical founding of Japan
- 2663 years ago
- Foundation of Rome
- 2756 years ago
- Beginning of Xia Dynasty in China
- 4104 years ago
- First Egyptian pyramid completed
- 4614 years ago
- End of the Paleolithic Period
- 12003 years ago