Have you ever stopped to think about how many hours are in a year? Or how many of those hours we spend working? This is a straightforward time conversion. Not only does it give useful information, but it’s a great way of practicing unit conversions. Also, knowing how many hours you work makes calculating your annual income easier if you get paid hourly.
Hours in a Year
To begin, a regular year has 365 days. The number of hours in a year is the number of days multiplied by number of hours in a day:
- Number of days in a year: 365 days
- Number of hours in a day: 24 hours
Using the formula:
Total hours in a year = Number of days × Number of hours in a day
Total hours in a year = 365 × 24 = 8,760 hours
So, there are 8,760 hours in a regular year.
Hours in a Leap Year
Every 4 years is a leap year, which has an extra day in February. So, a leap year has 366 days and an additional 24 hours in the year:
- Number of days in a leap year: 366 days
- Number of hours in a day: 24 hours
Using the formula:
Total hours in a leap year = 366 × 24 =8,784 hours
Therefore, there are 8,784 hours in a leap year.
Average Working Hours in a Year
For many, a standard workweek is 40 hours over five days. Estimate the number of working hours in a year using the number of weeks in a year and the number of work hours in a week:
- Number of weeks in a year: 52 weeks
- Number of working hours in a week: 40 hours
Total working hours in a year = 52 × 40 = 2,080 hours
So, on average, a person works 2,080 hours in a year, assuming a 40-hour work week. However, this is a rough estimate. The actual number of working days varies from one year to another due to the distribution of weekdays. Furthermore, many employees have days off for public holidays, vacations, or personal reasons.
Working Hours for Different Work Weeks
Not everyone who works has a 40-hour work week. Here are the number of work hours per year for longer hours or for part time work. Remember, there are 52 weeks in a year.
- 80-hour work week:
Total hours = 52 x 60 = 4,160 hours - 60-hour work week:
Total hours = 52 x 60 = 3,120 hours - 30-hour work week:
Total hours = 52 × 30 = 1,560 hours - 16-hour work week:
Total hours = 52 × 16 = 832 hours
How Many Hours Not-Working in a Year?
Okay, for a 40-hour week, assuming 8,760 hours worked a year, how many hours are not-working?
Let’s calculate the number of non-working hours in a year for a 40-hour work week, given that there are 8,760 hours in a year.
Total hours in a year: 8,760 hours
Working hours in a year (assuming 40-hour work week for 52 weeks): Total working hours in a year = 52 × 40 = 2,080 hours
Find the non-working hours by subtracting the working hours from the total hours in a year:
Non-working hours = Total hours in a year − Total working hours in a year
Non-working hours = 8,760 − 2,080 = 6,680 hours
Therefore, if you work a 40-hour work week, you have 6,680 non-working hours in a regular year of 8,760 hours.
Number of Work Hours in a Lifetime
Let’s calculate the estimated number of working hours in an average person’s life, assuming that they start working full-time at age 20 and retire at age 65.
Number of working years:
Age 65 – Age 20 = 45 years
Working hours in a year (assuming 40-hour work week for 52 weeks):
Total working hours in a year= 52 × 40 = 2,080 hours
Now, find the total working hours over a 45-year period:
Total working hours in a lifetime = Total working hours in a year × Number of working years
Total working hours in a lifetime = 2,080 × 45 = 93,600 hours
Therefore, over a span of 45 working years, an average person works approximately 93,600 hours in their lifetime.
References
- Doggett, L.E. (1992). “Calendars“. in Seidelmann, P. K. (ed.). Explanatory Supplement to the Astronomical Almanac (2nd ed.). Sausalito, CA: University Science Books.
- Maxwell, Brandt (2006). “Countries with days off from work besides Saturday and Sunday“.
- Pollard, A F (1940). “New Year’s Day and Leap Year in English History”. The English Historical Review. 55 (218): 177–193. doi:10.1093/ehr/LV.CCXVIII.177
- Zerubavel, Eviatar (1989). The Seven Day Circle: The History and Meaning of the Week. University of Chicago Press. ISBN 978-0-226-98165-9.