Back 1778 Abkhazian 1778 Afrikaans 1778 ALS 1778 እ.ኤ.አ. Amharic 1778 AN 1778 Arabic 1778 ARZ 1778 AST 1778 AVK 1778 Azerbaijani
| Millennium: | 2nd millennium |
|---|---|
| Centuries: | 17th century – 18th century – 19th century |
| Decades: | 1740s 1750s 1760s – 1770s – 1780s 1790s 1800s |
| Years: | 1775 1776 1777 – 1778 – 1779 1780 1781 |
| Gregorian calendar | 1778 MDCCLXXVIII |
| Ab urbe condita | 2531 |
| Armenian calendar | 1227 ԹՎ ՌՄԻԷ |
| Assyrian calendar | 6528 |
| Balinese saka calendar | 1699–1700 |
| Bengali calendar | 1185 |
| Berber calendar | 2728 |
| British Regnal year | 18 Geo. 3 – 19 Geo. 3 |
| Buddhist calendar | 2322 |
| Burmese calendar | 1140 |
| Byzantine calendar | 7286–7287 |
| Chinese calendar | 丁酉年 (Fire Rooster) 4474 or 4414 — to — 戊戌年 (Earth Dog) 4475 or 4415 |
| Coptic calendar | 1494–1495 |
| Discordian calendar | 2944 |
| Ethiopian calendar | 1770–1771 |
| Hebrew calendar | 5538–5539 |
| Hindu calendars | |
| - Vikram Samvat | 1834–1835 |
| - Shaka Samvat | 1699–1700 |
| - Kali Yuga | 4878–4879 |
| Holocene calendar | 11778 |
| Igbo calendar | 778–779 |
| Iranian calendar | 1156–1157 |
| Islamic calendar | 1191–1192 |
| Japanese calendar | An'ei 7 (安永７年) |
| Javanese calendar | 1703–1704 |
| Julian calendar | Gregorian minus 11 days |
| Korean calendar | 4111 |
| Minguo calendar | 134 before ROC 民前134年 |
| Nanakshahi calendar | 310 |
| Thai solar calendar | 2320–2321 |
| Tibetan calendar | 阴火鸡年 (female Fire-Rooster) 1904 or 1523 or 751 — to — 阳土狗年 (male Earth-Dog) 1905 or 1524 or 752 |
1778 (MDCCLXXVIII) was a common year starting on Thursday of the Gregorian calendar and a common year starting on Monday of the Julian calendar, the 1778th year of the Common Era (CE) and Anno Domini (AD) designations, the 778th year of the 2nd millennium, the 78th year of the 18th century, and the 9th year of the 1770s decade. As of the start of 1778, the Gregorian calendar was 11 days ahead of the Julian calendar, which remained in localized use until 1923.