This calculator calculates the hour difference between two times in a day. It is accurate to the minute and provides the time period in total hours and minutes, decimal hours, and total minutes. You can use this hours calculator to help generate an invoice, time sheet, or time card. If you’re always wondering “how many hours am I working,” this is the tool for you.
When using this hours calculator, only input numbers such as 1230 for 12:30 or 215 for 2:15. Input the start time and end time without using a period or colon (:).
If you input a single integer from 1 through 12 it will assume 1:00 through 12:00.
The hours calculator uses a 12-hour clock, using the numbers 1-12, where noon is 12 pm and midnight is 12 am. “am” stands for “anti meridiem” (before midday), while “pm” stands for post meridiem (after midday).
Decimal Hours Conversion
Decimal hours are found by dividing the minutes by 60. So if you worked for 1 hour and 20 minutes, divide 20 by 60 for 0.33 work hours and a total of 1.33 work hours. Decimal hours are important for calculating hourly pay.
If you need to convert decimal hours to minutes again, simply multiple your decimal hours by 60. For example, if you worked for 0.25 decimal hours, 60 x 0.25 = 15 minutes.
Common Time Periods in Hours
| Time Frame | Hours |
|---|---|
| Hours in a day | 24 |
| Hours in a week | 168 |
| Hours in a 30-day month | 720 |
| Hours in a 31-day month | 744 |
| Hours in an average month | 730 |
| Hours in a 365-day year | 8,760 |
| Hours in a leap year | 8,784 |
| Hours in an average year | 8,766 |
| Hours in a decade | 87,660 |
| Hours in a century | 876,600 |
How Do You Calculate Hours Between Times?
To calculate hours between times, determine the difference between the start time and the end time. For example, if you start work at 9:30 am and finish work at 5:15 pm, you subtract 5 hours and 15 minutes from the end time to reach 12 pm (noon) and then subtract another 2 hours and 30 minutes to reach 9:30 am, for a total of 7 hours and 45 minutes.
If your working time inlcudes breaks, subtract the total break time from the total work hours. For example, if you worked from 9 pm to 5 pm (8 hours) but had 30 minutes of break time, your total work time is 7 hours and 30 minutes.
Author
Chris Kolmar is a co-founder of Zippia and the editor-in-chief of the Zippia career advice blog. He has hired over 50 people in his career, been hired five times, and wants to help you land your next job. His research has been featured on the New York Times, Thrillist, VOX, The Atlantic, and a host of local news. More recently, he's been quoted on USA Today, BusinessInsider, and CNBC.
