How to Calculate Work Hours With an Unpaid Lunch Break

To work out your paid hours, take the time between the start and end of your shift, then subtract only the break time that is genuinely unpaid.

The arithmetic is simple. What makes a time card confusing is overnight shifts, decimal hours, and knowing which breaks should have been unpaid in the first place.

The formula

Paid time = end time - start time - unpaid break.

A shift from 9:00 AM to 5:30 PM is 8 hours 30 minutes. Take off a 30 minute unpaid lunch and you are paid for 8 hours, or 8.0 in decimal.

Step by step

1. Write your start and end times in the same format, either 12 hour or 24 hour. Mixing them is where errors start.
2. Find the total time between them.
3. Subtract the minutes for any break that is correctly unpaid.
4. Convert what is left to a decimal if your payroll system needs it.

When should a lunch break be unpaid?

Under general federal guidance, short rest breaks of about 20 minutes or less usually count as paid working time. A real meal break, normally 30 minutes or more, generally does not have to be paid when you are completely free from duty.

That last part matters more than people realize. A break is not unpaid just because it is on the schedule. If you are still answering calls, watching equipment, or serving customers while you eat, that time may still count as hours worked.

I cannot tell you whether your break should be unpaid. That depends on what you were actually doing and where you work, and state rules can be stricter than the federal position. Use this for the arithmetic and check the treatment with your payroll team.

How to calculate an overnight shift

When the end time is earlier than the start time, the end belongs to the next day. A shift from 10:00 PM to 6:00 AM is 8 hours. After a 30 minute unpaid break, you are paid for 7 hours 30 minutes.

Convert minutes to decimal hours

Divide the minutes by 60. So 15 minutes is 0.25, 30 minutes is 0.5, and 45 minutes is 0.75. That makes 7 hours 30 minutes into 7.5 decimal hours.

Mistakes that cost you

• Writing 7 hours 30 minutes as 7.30. In decimal it is 7.5, and the difference is real money.
• Subtracting a short paid rest break as though it were an unpaid meal break.
• Forgetting that an end time after midnight belongs to the following day.
• Rounding each shift a different way instead of following one consistent policy.

Do one shift or a whole week

The Work Hours Calculator handles a single shift. Use the Time Card Calculator when you need to add up several days, compare the total against the overtime line, and estimate gross pay. If the decimal part is what is tripping you up, the Decimal Hours Converter does just that piece.