How Do I Calculate My Work Hours

Work Hours Calculator

Use this calculator to determine the total number of hours worked, accounting for start time, end time, and any breaks taken.

Understanding Your Work Hours

Accurately calculating work hours is crucial for various reasons, including payroll, time management, and ensuring compliance with labor laws. Whether you're an employee tracking your time or an employer managing staff, understanding the exact duration of a work shift is fundamental.

How to Calculate Work Hours Manually

The basic formula for calculating work hours involves subtracting the start time from the end time and then deducting any break periods. However, this can become tricky with shifts that cross midnight or when dealing with different time formats.

  1. Convert Times to a Common Unit: It's easiest to convert both start and end times into minutes from midnight. For example, 9:00 AM is 9 * 60 = 540 minutes, and 5:00 PM (17:00) is 17 * 60 = 1020 minutes.
  2. Calculate Gross Duration: Subtract the start time (in minutes) from the end time (in minutes). If the end time is numerically smaller than the start time (indicating an overnight shift), add 24 hours (1440 minutes) to the end time before subtracting.
  3. Subtract Breaks: Deduct the total duration of all breaks taken during the shift from the gross duration. Ensure breaks are also in minutes.
  4. Convert Back to Hours and Minutes: Divide the final net duration by 60 to get the hours, and the remainder will be the minutes.

Example Calculation

Let's say an employee works from 9:00 AM to 5:30 PM and takes a 45-minute lunch break.

  • Start Time: 9:00 AM = 9 * 60 = 540 minutes from midnight.
  • End Time: 5:30 PM (17:30) = (17 * 60) + 30 = 1020 + 30 = 1050 minutes from midnight.
  • Gross Duration: 1050 – 540 = 510 minutes.
  • Break Duration: 45 minutes.
  • Net Work Duration: 510 – 45 = 465 minutes.
  • Convert to Hours and Minutes: 465 minutes / 60 = 7 with a remainder of 45. So, 7 hours and 45 minutes.

For an overnight shift, consider working from 10:00 PM to 6:00 AM with a 30-minute break.

  • Start Time: 10:00 PM (22:00) = 22 * 60 = 1320 minutes.
  • End Time: 6:00 AM (06:00) = 6 * 60 = 360 minutes.
  • Since 360 < 1320, it's an overnight shift. Add 24 hours to end time: 360 + (24 * 60) = 360 + 1440 = 1800 minutes.
  • Gross Duration: 1800 – 1320 = 480 minutes.
  • Break Duration: 30 minutes.
  • Net Work Duration: 480 – 30 = 450 minutes.
  • Convert to Hours and Minutes: 450 minutes / 60 = 7 with a remainder of 30. So, 7 hours and 30 minutes.

This calculator simplifies these calculations, providing a quick and accurate way to determine total work hours.

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