Time Card Calculator

Work out hours worked from a shift.

Clock in

24-hour format, HH:MM

Clock out

24-hour format, HH:MM

Unpaid break(optional)

min

Results update as you type.

Hours worked

—

In H:MM—

How it works

A time card calculator turns a shift's clock-in and clock-out times, minus any unpaid break, into the hours worked, shown both as a decimal figure for payroll and as hours and minutes for reading. It converts each time to minutes past midnight, finds the gap, and when the clock-out is earlier than the clock-in it adds a full day so an overnight shift is measured correctly instead of showing a negative span. This is the everyday arithmetic behind wages, and small errors compound fast. Misreading a shift that runs past midnight, or forgetting to deduct a lunch break, feeds straight into over- or under-payment and disputes. Because clock time is base-60 rather than decimal, subtracting HH:MM values directly gives wrong answers, so converting to a single unit of minutes first is what keeps the result honest. The decimal-hours output is deliberately the primary figure because payroll and invoicing systems multiply decimal hours by an hourly rate: 8 hours 30 minutes is 8.5, not 8.30. The H:MM view is there for a human sanity check. Shift workers verifying a paycheck, small-business owners running payroll, and freelancers logging billable time use a time card calculator to convert raw punches into the exact paid hours, one shift at a time, with unpaid breaks removed.

Formula

hours = (clockOut − clockIn, +24h if overnight) − break; shown as decimal and H:MM

Both clock times are converted to minutes since midnight and subtracted. If the result is negative the shift crossed midnight, so 1,440 minutes — one full day — is added to make it positive. The unpaid break in minutes is then subtracted, and the remaining minutes are divided by sixty for decimal hours and split into whole hours and minutes for the H:MM view. Working in a single minute unit avoids mixing base-60 clock fields.

Source:Standard timekeeping arithmetic

We review all our tools from time to time to ensure accuracy.

Worked example

Clock in:09:00Clock out:17:30Unpaid break:30

09:00 to 17:30 is 8.5 hours; a 30-minute unpaid break leaves 8.00 hours (8:00).

How to use this calculator

1
Enter your values
Enter clock in and clock out.
2
Adjust the options
Adjust unpaid break if they apply — sensible defaults are already set.
3
Read your result
Hours worked updates instantly as you type — no button to press.

Frequently asked questions

How do I enter the times?

Use 24-hour format as HH:MM, so 9 in the morning is 09:00 and half past five in the afternoon is 17:30. For PM times, add twelve to the hour: 1:15 PM is 13:15 and 11:45 PM is 23:45, while midnight is 00:00. Entering times this way removes any AM/PM ambiguity and lets the calculator handle overnight shifts correctly by comparing the two values directly.

Does it handle overnight shifts?

Yes. When the clock-out time is earlier than the clock-in time, the calculator assumes the shift ran past midnight and adds 24 hours, so a shift from 22:00 to 06:00 reads as eight hours rather than a negative figure. This makes it reliable for night shifts and on-call windows. It assumes a single shift under 24 hours long, which covers essentially all real work patterns.

What are decimal hours and why are they primary?

Decimal hours express minutes as a fraction of an hour, so 8 hours 30 minutes is 8.5 and 15 minutes is 0.25. Payroll and invoicing systems use this form because it multiplies directly by an hourly rate, whereas 8:30 does not. That is why the decimal figure is the main result and the H:MM value is provided alongside only as an easy-to-read cross-check.

How is the unpaid break treated?

The break, entered in minutes, is subtracted from the elapsed shift time, because unpaid meal and rest breaks are not counted as worked hours. A 09:00–17:30 shift is 8.5 hours of elapsed time, but a 30-minute unpaid break leaves 8.00 paid hours. If your break is paid, enter zero so the full elapsed time is counted. Leaving the field blank treats the break as zero.

Can I total a whole week with this?

Run each shift separately and add the decimal-hours results to get a weekly total, which is the form most payroll systems expect. Keep breaks deducted per shift before summing. If weekly hours exceed the overtime threshold, typically 40 in the US, split the excess into overtime and apply the premium rate separately, since this calculator reports worked hours rather than pay.