How Long is a Decade? 

How long is a decade? A decade is a measure of time that is equal to 10 years, 120 months, about 521.785 weeks, or about 3650 days.

• From January 1, 1990 to December 31, 1999, there is a decade.

• From January 1, 1995 to December 31, 2004, there is a decade.

• From January 1, 1960 to December 31, 1969, there is a decade.

Did you know this?

When people say from the 1980s, 1970s, or 1990s, they are referring to a decade.

For example, from the 1970s means from 1970 to 1979. From 1970 to 1979, there are ten years.