820
| Millennium: | 1st millennium |
|---|---|
| Centuries: | 8th century – 9th century – 10th century |
| Decades: | 790s 800s 810s – 820s – 830s 840s 850s |
| Years: | 817 818 819 – 820 – 821 822 823 |
| Gregorian calendar | 820 DCCCXX |
| Ab urbe condita | 1573 |
| Armenian calendar | 269 ԹՎ ՄԿԹ |
| Assyrian calendar | 5570 |
| Balinese saka calendar | 741–742 |
| Bengali calendar | 227 |
| Berber calendar | 1770 |
| Buddhist calendar | 1364 |
| Burmese calendar | 182 |
| Byzantine calendar | 6328–6329 |
| Chinese calendar | 己亥年 (Earth Pig) 3516 or 3456 — to — 庚子年 (Metal Rat) 3517 or 3457 |
| Coptic calendar | 536–537 |
| Discordian calendar | 1986 |
| Ethiopian calendar | 812–813 |
| Hebrew calendar | 4580–4581 |
| Hindu calendars | |
| - Vikram Samvat | 876–877 |
| - Shaka Samvat | 741–742 |
| - Kali Yuga | 3920–3921 |
| Holocene calendar | 10820 |
| Iranian calendar | 198–199 |
| Islamic calendar | 204–205 |
| Japanese calendar | Kōnin 11 (弘仁１１年) |
| Javanese calendar | 716–717 |
| Julian calendar | 820 DCCCXX |
| Korean calendar | 3153 |
| Minguo calendar | 1092 before ROC 民前1092年 |
| Nanakshahi calendar | −648 |
| Seleucid era | 1131/1132 AG |
| Thai solar calendar | 1362–1363 |
| Tibetan calendar | 阴土猪年 (female Earth-Pig) 946 or 565 or −207 — to — 阳金鼠年 (male Iron-Rat) 947 or 566 or −206 |
Events
Births
Deaths
- Religious philosopher Adi Shankara dies.