2040s
| Millennium: | 3rd millennium |
| Centuries: | 20th century – 21st century – 22nd century |
| Decades: | 2010s 2020s 2030s – 2040s – 2050s 2060s 2070s |
| Years: | 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 |
The 2040s will begin on January 1, 2040 and end on December 31, 2049. It is distinct from the decade known as the '''205st decade''' which began on January 1, 2041 and ended on December 31, 2050.
The decade as a whole[change | change source]
This decade will be called "the twenty-forties". The Roman number will be MMXL.
The first baby boomers will be 100 years old in 2046.