| Millennium: | 1st millennium |
|---|---|
| Centuries: | |
| Decades: | |
| Years: |
| Gregorian calendar | 839 DCCCXXXIX |
| Ab urbe condita | 1592 |
| Armenian calendar | 288 ԹՎ ՄՁԸ |
| Assyrian calendar | 5589 |
| Bengali calendar | 246 |
| Berber calendar | 1789 |
| Buddhist calendar | 1383 |
| Burmese calendar | 201 |
| Byzantine calendar | 6347–6348 |
| Chinese calendar |
戊午年 (Earth Horse) 3535 or 3475 — to — 己未年 (Earth Goat) 3536 or 3476 |
| Coptic calendar | 555–556 |
| Discordian calendar | 2005 |
| Ethiopian calendar | 831–832 |
| Hebrew calendar | 4599–4600 |
| Hindu calendars | |
| - Vikram Samvat | 895–896 |
| - Shaka Samvat | 760–761 |
| - Kali Yuga | 3939–3940 |
| Holocene calendar | 10839 |
| Iranian calendar | 217–218 |
| Islamic calendar | 224–225 |
| Japanese calendar |
Jōwa 6 (承和6年) |
| Javanese calendar | 736–737 |
| Julian calendar | 839 DCCCXXXIX |
| Korean calendar | 3172 |
| Minguo calendar | 1073 before ROC 民前1073年 |
| Nanakshahi calendar | −629 |
| Seleucid era | 1150/1151 AG |
| Thai solar calendar | 1381–1382 |
Year 839 (DCCCXXXIX) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar.