To determine how many hours are in a year, we multiply the number hours in a day by the number of days in years.

## One Year

## =

## 8760 Hours

The number of hours in a year will depend on the type of calendars such as Gregorian, Julian, Sidereal, and Tropical. There are two types of calendars in the Gregorian calendar, the common year which has 365 days and the leap year, 366 days. To determine how many hours are in a year, we multiply the number hours in a day by the number of days in years.

### Time Conversion Calculator

#### The Gregorian calendar year

One common year in the Gregorian calendar has 365 days. If we want to find the number of hours that are in this year we multiply 365 days by the number of hours in a day. This can be expressed as;

1 common year = 365 days = 365 days x 24 hours/day

= 8760 hours

For the leap year, a single day is added in February to give a total number of 366 days in a year. This can be expressed as;

1 leap year = 366 days = 366 x 24 hours/ day

= 8784 hours

One mean calendar year is estimated to have 365.2425 days. Its calculation will be;

1 mean year = 365 + ¼ -1/100 + 1/400 days

= 365.2425 x 24 hours/day

= 8765.82 hours

#### The Julian Year

The Julian year calendar is mostly used for astronomical calculations and it has 365.25 days. To determine the number of hours in a Julian year, we multiply 365.25 by the number of hours in a day. This can be expressed as;

1 Julian year = 365.25 x 24 hours/ day

= 8766 hours

#### The Sidereal year

This calendar is mostly used by the astronomers. It is the approximation of the time that the Earth takes to perform a single rotation around the sun. One sidereal year is equivalent to 365.25636 days. It will be expressed as;

1 Sidereal year = 365.25636 x 24 hours per day

= 8766.15264 hours

#### The Tropical year

A single tropical year is estimated to be the time the Earth takes to complete a single rotation or cycle of the 4 seasons i.e. spring, summer, autumn, and winter. One tropical year has 365.242189 days. To determine the number of hours in one tropical year, we multiply 365.242189 by the number of hours in a day. It can be expressed as;

1 Tropical year = 365. 242189 x 24 hours per day

= 8765.812536 hours