This calculator finds the elapsed time between a clock-in and clock-out time, handling shifts that cross midnight, and subtracts any unpaid break to give total hours worked.
Time Card Calculator
Total hours worked in a day from clock-in and clock-out times, minus any unpaid break.
What the Timecard Calculator Does
This calculator covers timecard hour calculations, clock-in/clock-out conversions, and payroll time tracking — converting raw punch times into decimal hours worked, which is how most payroll systems calculate pay. It handles both same-day shifts and overnight shifts that cross midnight, and subtracts any unpaid break automatically.
Employees checking their own pay, and small-business owners running payroll by hand, both use this kind of calculation regularly to turn a punch clock’s raw in/out times into billable or payable hours.
How Hours Worked Are Calculated
Formula
Hours Worked = (Clock Out − Clock In, or Clock Out + 24 − Clock In if overnight) − Break (in hours)
Where:
- Clock In / Clock Out = 24-hour clock times
- The +24 adjustment applies only when the clock-out time is numerically earlier than the clock-in time, which happens when a shift crosses midnight
- Break = unpaid break minutes converted to hours
Worked Example
You clock in at 9:00 AM (9.0) and clock out at 5:30 PM (17.5), with a 30-minute unpaid lunch.
Hours Worked = (17.5 − 9.0) − 0.5 = 8.5 − 0.5 = 8.0 hours
That’s a full 8-hour workday once the unpaid lunch break is subtracted from the raw 8.5 hours between clock-in and clock-out.
Handling Overnight Shifts
If you clock in at 10:00 PM (22.0) and clock out at 6:00 AM (6.0) the next day, a simple subtraction would give a negative number. The calculator detects this and adds 24 hours to the clock-out time first: (6.0 + 24 − 22.0) = 8.0 hours, correctly capturing the overnight span.
Frequently Asked Questions
How do I enter a time like 8:15 as a decimal?
Convert minutes to a decimal fraction of an hour by dividing by 60 — 15 minutes is 15 ÷ 60 = 0.25, so 8:15 becomes 8.25.
Does this calculator round to the nearest quarter hour?
No — it returns the exact decimal hours worked. Some payroll systems round punch times to the nearest 6 or 15 minutes before calculating pay; check your employer’s specific rounding policy if your paycheck doesn’t match this exact figure.
What if I have more than one unpaid break in a shift?
Add up all unpaid break minutes into a single total before entering them, since the calculator subtracts one combined break figure from the total elapsed time.
Why would my calculated hours not match my paycheck?
Differences usually come from rounding rules, paid vs. unpaid break classifications, or overtime rules your employer applies — this calculator only performs the raw elapsed-time math, not payroll-specific adjustments.
How do I calculate a full week’s timecard total?
Run the calculation once per shift, then add each day’s resulting hours together for a weekly total. Tracking each day separately also makes it easier to spot a single mispunched entry if your weekly total looks off.