Work Hours Calculator
Work out how many hours you worked between two times, minus breaks — overnight shifts included.
How to use
- Enter your shift start time and end time.
- Add your total break time in minutes (leave 0 for no break).
- Read the net working time — also shown as decimal hours for timesheets and payroll.
Examples
Standard office day
09:00 to 18:00 with a 60-minute lunch is 9 hours gross and 8 hours net (8.00 decimal hours).
Overnight shift
22:00 to 06:00 with a 30-minute break crosses midnight: 8 hours gross, 7 hours 30 minutes net (7.5 decimal hours).
A standard Korean workday
A 09:00 to 18:00 shift with a one-hour lunch break gives eight paid hours, which is the statutory daily limit. Korean law requires at least 30 minutes of break for every four hours worked and one hour for every eight, and break time is unpaid, which is why the nine-hour span pays eight.
Overtime over the 52-hour week
The statutory limit is 40 hours per week plus up to 12 hours of agreed overtime, giving 52. Totalling each day and adding them up shows where a week sits against that ceiling. Overtime hours are paid at 1.5 times the normal rate, and hours worked on a holiday carry their own premium on top.
Part-time and the weekly paid rest day
An employee who works at least 15 hours a week and completes their scheduled days earns a paid weekly rest day (주휴수당), worth one day of their average hours. Totalling a part-time week is how you check whether it clears the 15-hour line, which is why some schedules are deliberately built just under it.
FAQ
How does the overnight shift calculation work?
When the end time is earlier than the start time, the calculator assumes the shift crosses midnight and adds 24 hours. 22:00 to 06:00 is therefore treated as 8 hours, and the result is marked as an overnight shift.
What are decimal hours and why do timesheets use them?
Decimal hours express minutes as a fraction of an hour: 7 hours 30 minutes is 7.5 decimal hours. Payroll systems multiply decimal hours by an hourly rate, which is why timesheets prefer this format.
Is the break subtracted automatically?
Yes. Net working time = time between start and end minus the break you enter. The gross duration and the break are shown separately, so you can verify the numbers.
What if my break is longer than the shift?
That would give negative working time, so the calculator flags it as an error instead of showing a misleading result.
Can I calculate multiple shifts or a whole week?
This page calculates one shift at a time. Run each shift and add the decimal hours together — a weekly version is a planned addition.
How is overtime pay calculated in Korea?
Work beyond eight hours a day or 40 hours a week is paid at 1.5 times the ordinary hourly wage. Night work between 22:00 and 06:00 adds another 0.5 times, so night overtime reaches 2.0. Holiday work is 1.5 times for the first eight hours and 2.0 beyond that. These premiums apply to workplaces with five or more employees.
Does the calculator know about my pay rate?
No — it totals time only. It gives you the hours figure that a payroll calculation starts from, in both hours-and-minutes and decimal form. Converting that into pay requires your ordinary hourly wage and which premium bands apply, both of which depend on your contract and workplace size.
What counts as working time when I am on standby?
Time you are required to remain available to the employer generally counts as working time even if there is nothing to do, whereas a break you can actually use freely does not. The practical test is whether you are free to leave. Because that line is often disputed, record the actual span and the break separately rather than netting them in your head.