| Years |
|---|
| Millennium |
| 2nd millennium |
| Centuries |
| Decades |
| Years |
| Gregorian calendar | 1340 MCCCXL |
| Ab urbe condita | 2093 |
| Armenian calendar | 789 ԹՎ ՉՁԹ |
| Assyrian calendar | 6090 |
| Balinese saka calendar | 1261–1262 |
| Bengali calendar | 747 |
| Berber calendar | 2290 |
| English Regnal year | 13 Edw. 3 – 14 Edw. 3 |
| Buddhist calendar | 1884 |
| Burmese calendar | 702 |
| Byzantine calendar | 6848–6849 |
| Chinese calendar | 己卯年 (Earth Rabbit) 4036 or 3976 — to — 庚辰年 (Metal Dragon) 4037 or 3977 |
| Coptic calendar | 1056–1057 |
| Discordian calendar | 2506 |
| Ethiopian calendar | 1332–1333 |
| Hebrew calendar | 5100–5101 |
| Hindu calendars | |
| - Vikram Samvat | 1396–1397 |
| - Shaka Samvat | 1261–1262 |
| - Kali Yuga | 4440–4441 |
| Holocene calendar | 11340 |
| Igbo calendar | 340–341 |
| Iranian calendar | 718–719 |
| Islamic calendar | 740–741 |
| Japanese calendar | Ryakuō 3 (暦応３年) |
| Javanese calendar | 1252–1253 |
| Julian calendar | 1340 MCCCXL |
| Korean calendar | 3673 |
| Minguo calendar | 572 before ROC 民前572年 |
| Nanakshahi calendar | −128 |
| Thai solar calendar | 1882–1883 |
| Tibetan calendar | ས་མོ་ཡོས་ལོ་ (female Earth-Hare) 1466 or 1085 or 313 — to — ལྕགས་ཕོ་འབྲུག་ལོ་ (male Iron-Dragon) 1467 or 1086 or 314 |
1340 (MCCCXL) was a leap year starting on Saturday of the Julian calendar, the 1340th year of the Common Era (CE) and Anno Domini (AD) designations, the 340th year of the 2nd millennium, the 40th year of the 14th century, and the 1st year of the 1340s decade. As of the start of 1340, the Gregorian calendar was 8 days ahead of the Julian calendar, which was the dominant calendar of the time.