| Centuries: | 6th century · 7th century · 8th century |
| Decades: | 630s 640s 650s 660s 670s 680s 690s |
| Years: | 661 662 663 664 665 666 667 |
| 664 by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishment and disestablishment categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 664 DCLXIV |
| Ab urbe condita | 1417 |
| Armenian calendar | 113 ԹՎ ՃԺԳ |
| Bahá'í calendar | -1180 – -1179 |
| Bengali calendar | 71 |
| Berber calendar | 1614 |
| Buddhist calendar | 1208 |
| Burmese calendar | 26 |
| Byzantine calendar | 6172 – 6173 |
| Chinese calendar | 癸亥年十一月廿八日 (3300/3360-11-28) — to —
甲子年十二月初九日(3301/3361-12-9) |
| Coptic calendar | 380 – 381 |
| Ethiopian calendar | 656 – 657 |
| Hebrew calendar | 4424 – 4425 |
| Hindu calendars | |
| - Bikram Samwat | 720 – 721 |
| - Shaka Samvat | 586 – 587 |
| - Kali Yuga | 3765 – 3766 |
| Holocene calendar | 10664 |
| Iranian calendar | 42 – 43 |
| Islamic calendar | 43 – 44 |
| Japanese calendar | |
| Korean calendar | 2997 |
| Thai solar calendar | 1207 |