| Millennium: | 4th Millennium BC |
|---|---|
| Centuries: | 38th cent. BC – 37th cent. BC – 36th cent. BC |
| Decades: | 3710s BC 3700s BC 3690s BC – 3680s BC – 3670s BC 3660s BC 3650s BC |
| Years: | 3689 BC 3688 BC 3687 BC – 3686 BC – 3685 BC 3684 BC 3683 BC |
| Gregorian calendar | 3686 MMMDCLXXXVI |
| Ab urbe condita | 4439 |
| Armenian calendar | 3135 ԹՎ ՎՃԼԵ |
| Assyrian calendar | 8436 |
| Bahá'í calendar | 1842–1843 |
| Bengali calendar | 3093 |
| Berber calendar | 4636 |
| British Regnal year | N/A |
| Buddhist calendar | 4230 |
| Burmese calendar | 3048 |
| Byzantine calendar | 9194–9195 |
| Chinese calendar | 乙酉年 (Wood Rooster) 6382 or 6322 — to — 丙戌年 (Fire Dog) 6383 or 6323 |
| Coptic calendar | 3402–3403 |
| Discordian calendar | 4852 |
| Ethiopian calendar | 3678–3679 |
| Hebrew calendar | 7446–7447 |
| Hindu calendars | |
| - Vikram Samvat | 3742–3743 |
| - Shaka Samvat | 3607–3608 |
| - Kali Yuga | 6786–6787 |
| Holocene calendar | 13686 |
| Igbo calendar | 2686–2687 |
| Iranian calendar | 3064–3065 |
| Islamic calendar | 3158–3159 |
| Japanese calendar | Heisei 1698 (平成１６９８年) |
| Javanese calendar | 3670–3671 |
| Juche calendar | 1775 |
| Julian calendar | Gregorian minus 25 days |
| Korean calendar | 6019 |
| Minguo calendar | ROC 1775 民國1775年 |
| Nanakshahi calendar | 2218 |
| Thai solar calendar | 4229 |
| Unix time | 54151804800–54183340799 |
The year 3686 BC