| Millennium: | 3rd Millennium BC |
|---|---|
| Centuries: | 28th cent. BC – 27th cent. BC – 26th cent. BC |
| Decades: | 2690s BC 2680s BC 2670s BC – 2660s BC – 2650s BC 2640s BC 2630s BC |
| Years: | 2663 BC 2662 BC 2661 BC – 2660 BC – 2659 BC 2658 BC 2657 BC |
| Gregorian calendar | 2660 MMDCLX |
| Ab urbe condita | 3413 |
| Armenian calendar | 2109 ԹՎ ՍՃԹ |
| Assyrian calendar | 7410 |
| Bahá'í calendar | 816–817 |
| Bengali calendar | 2067 |
| Berber calendar | 3610 |
| British Regnal year | N/A |
| Buddhist calendar | 3204 |
| Burmese calendar | 2022 |
| Byzantine calendar | 8168–8169 |
| Chinese calendar | 己卯年 (Earth Rabbit) 5356 or 5296 — to — 庚辰年 (Metal Dragon) 5357 or 5297 |
| Coptic calendar | 2376–2377 |
| Discordian calendar | 3826 |
| Ethiopian calendar | 2652–2653 |
| Hebrew calendar | 6420–6421 |
| Hindu calendars | |
| - Vikram Samvat | 2716–2717 |
| - Shaka Samvat | 2581–2582 |
| - Kali Yuga | 5760–5761 |
| Holocene calendar | 12660 |
| Igbo calendar | 1660–1661 |
| Iranian calendar | 2038–2039 |
| Islamic calendar | 2100–2102 |
| Japanese calendar | Heisei 672 (平成６７２年) |
| Javanese calendar | 2612–2613 |
| Juche calendar | 749 |
| Julian calendar | Gregorian minus 18 days |
| Korean calendar | 4993 |
| Minguo calendar | ROC 749 民國749年 |
| Nanakshahi calendar | 1192 |
| Thai solar calendar | 3203 |
| Unix time | 21774268800–21805891199 |
The year 2660 BC