| Centuries: | 3rd century · 4th century · 5th century |
| Decades: | 270s 280s 290s 300s 310s 320s 330s |
| Years: | 301 302 303 304 305 306 307 |
| 304 by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishment and disestablishment categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 304 CCCIV |
| Ab urbe condita | 1057 |
| Armenian calendar | N/A |
| Bahá'í calendar | -1540 – -1539 |
| Bengali calendar | -289 |
| Berber calendar | 1254 |
| Buddhist calendar | 848 |
| Burmese calendar | -334 |
| Byzantine calendar | 5812 – 5813 |
| Chinese calendar | 癸亥年十二月初八日 (2940/3000-12-8) — to —
甲子年十一月十八日(2941/3001-11-18) |
| Coptic calendar | 20 – 21 |
| Ethiopian calendar | 296 – 297 |
| Hebrew calendar | 4064 – 4065 |
| Hindu calendars | |
| - Bikram Samwat | 360 – 361 |
| - Shaka Samvat | 226 – 227 |
| - Kali Yuga | 3405 – 3406 |
| Holocene calendar | 10304 |
| Iranian calendar | 318 BP – 317 BP |
| Islamic calendar | 328 BH – 327 BH |
| Japanese calendar | |
| Korean calendar | 2637 |
| Thai solar calendar | 847 |