What Is a Hours Calculator?
A hours calculator computes the total number of hours and minutes worked between a start time and an end time, with an optional deduction for lunch or other breaks. It is perfect for employees tracking their workday, freelancers billing by the hour, payroll administrators, and anyone who needs to quickly figure out time worked.
How to Calculate Hours Worked
To find how many hours you worked, subtract your start time from your end time. If the minutes of the end time are less than the minutes of the start time, borrow 60 minutes from the hour column. Then subtract the break duration from the total to get net hours worked. For example, if you start at 8:30 AM, finish at 5:00 PM, and take a 1-hour lunch:
- Convert to 24-hour: 08:30 to 17:00
- Borrow 1 hour: 16 h 60 min − 8 h 30 min = 8 h 30 min
- Subtract 1-hour lunch: 8 h 30 min − 1 h 00 min = 7 h 30 min
- You worked 7.5 hours (7 hours 30 minutes)
Decimal Hours for Payroll
For payroll and billing, hours are usually expressed in decimal form. To convert minutes to decimal hours, divide by 60. Common conversions include: 15 min = 0.25 h, 30 min = 0.50 h, 45 min = 0.75 h. So 7 hours 30 minutes becomes 7.50 hours, which you multiply by your hourly rate to calculate gross pay.
Why Use a Time Card Calculator?
- Avoids arithmetic errors when adding and subtracting times
- Handles overnight shifts automatically
- Automatically deducts lunch breaks
- Gives both hh:mm and decimal hour formats for different uses
- Saves time for payroll staff and freelancers
- Helps employees verify their paycheck
Overtime Calculations
In the United States, the Fair Labor Standards Act (FLSA) requires non-exempt employees to receive overtime pay of at least 1.5 times their regular rate for hours worked beyond 40 in a workweek. To calculate overtime pay: (hours worked − 40) × hourly rate × 1.5. Some states have stricter rules, including daily overtime (over 8 hours in a day) in California and several other states.
Tips for Accurate Time Tracking
- Record exact start and end times — round only at the end if needed
- Be consistent about whether you deduct break time
- Use the same time format (12-hour or 24-hour) throughout
- Double-check AM vs. PM entries
- For shifts crossing midnight, make sure the calculator handles that case
- Keep time records for at least 2-3 years for tax and compliance purposes
Common Work Schedules
A standard full-time workweek is 40 hours (8 hours/day × 5 days). A "9-to-5" job with a 1-hour lunch is actually 7 hours of work per day, or 35 hours per week. Part-time work is typically anything below 30-35 hours per week. Flexible schedules, compressed workweeks (4 10-hour days), and shift work all require careful hour tracking.
Frequently Asked Questions
How do I calculate my hourly rate from my salary?
Divide your annual salary by 2,080 (52 weeks × 40 hours). For example, a $52,000 salary ÷ 2,080 = $25 per hour.
Does lunch count as work time?
In most cases, no — a true lunch break where you are completely relieved of duties is unpaid. However, if you work through lunch or are on call during lunch, that time may be compensable. Check your local labor laws.
What about overnight shifts?
Overnight shifts (e.g., 11 PM to 7 AM) are calculated the same way — 8 hours total. The calculator adds 24 hours to the end time and then subtracts the start time.