645 BC
| Years |
|---|
| Millennium |
| 1st millennium BC |
| Centuries |
| Decades |
| Years |
| 645 BC by topic |
| Politics |
|---|
| Categories |
| Gregorian calendar | 645 BC DCXLV BC |
| Ab urbe condita | 109 |
| Ancient Egypt era | XXVI dynasty, 20 |
| - Pharaoh | Psamtik I, 20 |
| Ancient Greek Olympiad (summer) | 33rd Olympiad, year 4 |
| Assyrian calendar | 4106 |
| Balinese saka calendar | N/A |
| Bengali calendar | −1238 – −1237 |
| Berber calendar | 306 |
| Buddhist calendar | −100 |
| Burmese calendar | −1282 |
| Byzantine calendar | 4864–4865 |
| Chinese calendar | 乙亥年 (Wood Pig) 2053 or 1846 — to — 丙子年 (Fire Rat) 2054 or 1847 |
| Coptic calendar | −928 – −927 |
| Discordian calendar | 522 |
| Ethiopian calendar | −652 – −651 |
| Hebrew calendar | 3116–3117 |
| Hindu calendars | |
| - Vikram Samvat | −588 – −587 |
| - Shaka Samvat | N/A |
| - Kali Yuga | 2456–2457 |
| Holocene calendar | 9356 |
| Iranian calendar | 1266 BP – 1265 BP |
| Islamic calendar | 1305 BH – 1304 BH |
| Javanese calendar | N/A |
| Julian calendar | N/A |
| Korean calendar | 1689 |
| Minguo calendar | 2556 before ROC 民前2556年 |
| Nanakshahi calendar | −2112 |
| Thai solar calendar | −102 – −101 |
| Tibetan calendar | 阴木猪年 (female Wood-Pig) −518 or −899 or −1671 — to — 阳火鼠年 (male Fire-Rat) −517 or −898 or −1670 |
The year 645 BC was a year of the pre-Julian Roman calendar. In the Roman Empire, it was known as year 109 Ab urbe condita . The denomination 645 BC 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.