| Millennium: | 1st millennium |
|---|---|
| Centuries: | 7th century – 8th century – 9th century |
| Decades: | 690s 700s 710s – 720s – 730s 740s 750s |
| Years: | 718 719 720 – 721 – 722 723 724 |
| 721 by topic | |
| Politics | |
| State leaders – Sovereign states | |
| Birth and death categories | |
| Births – Deaths | |
| Establishment and disestablishment categories | |
| Establishments – Disestablishments | |
| Gregorian calendar | 721 DCCXXI |
| Ab urbe condita | 1474 |
| Armenian calendar | 170 ԹՎ ՃՀ |
| Bahá'í calendar | -1123 – -1122 |
| Bengali calendar | 128 |
| Berber calendar | 1671 |
| Buddhist calendar | 1265 |
| Burmese calendar | 83 |
| Byzantine calendar | 6229 – 6230 |
| Chinese calendar | 庚申年十一月廿九日 (3357/3417-11-29) — to —
辛酉年十二月初九日(3358/3418-12-9) |
| Coptic calendar | 437 – 438 |
| Ethiopian calendar | 713 – 714 |
| Hebrew calendar | 4481 – 4482 |
| Hindu calendars | |
| - Bikram Samwat | 777 – 778 |
| - Shaka Samvat | 643 – 644 |
| - Kali Yuga | 3822 – 3823 |
| Holocene calendar | 10721 |
| Iranian calendar | 99 – 100 |
| Islamic calendar | 102 – 103 |
| Japanese calendar | |
| Korean calendar | 3054 |
| Thai solar calendar | 1264 |