How to Calculate Hours Worked With Lunch Breaks (Steps + Examples)
Filling in a time card sounds easy until lunch breaks, odd start times and night shifts get involved. Was it 7.45 hours or 7.75? Does the 15-minute coffee break come off? What happens when your shift ends after midnight?
This guide shows the simple method that works for any shift, with worked examples, a minutes-to-decimal cheat sheet and the break rules you need to know.
The short answer
- Hours worked = end time − start time − unpaid breaks.
- Example: 9:00 AM to 5:30 PM is 8 hours 30 minutes. Take off a 30-minute lunch and you worked 8 hours.
- To pay or bill the time, turn minutes into decimals by dividing by 60: 45 minutes is 0.75 hours.
- Short paid breaks (like a 10-minute coffee break) usually stay in your hours. Only unpaid meal breaks come off.
How to calculate hours worked, step by step
- Write both times in 24-hour format. This avoids AM/PM mistakes. 5:30 PM becomes 17:30. (Add 12 to any PM hour except 12 PM.)
- Subtract the start time from the end time. 17:30 − 09:00 = 8 hours 30 minutes. If the minutes would go below zero, borrow 60 minutes from the hours.
- Take off unpaid breaks. 8 h 30 min − 30 min lunch = 8 h 0 min.
- Turn the minutes into a decimal. Divide the minutes by 60. 0 minutes is .00, so the answer is 8.00 hours. Multiply by your hourly rate to get your pay: 8.00 × $20 = $160.
Not sure about 24-hour time? Our military time converter turns any time into 24-hour format and back.
Worked examples for real shifts
| Shift | Unpaid break | Time on site | Hours worked | Decimal |
|---|---|---|---|---|
| 9:00 AM – 5:30 PM | 30 min | 8 h 30 min | 8 h | 8.00 |
| 8:15 AM – 4:45 PM | 45 min | 8 h 30 min | 7 h 45 min | 7.75 |
| 9:00 AM – 5:00 PM | 30 min | 8 h | 7 h 30 min | 7.50 |
| 7:00 AM – 3:30 PM (plus two paid 15-min breaks) | 30 min | 8 h 30 min | 8 h | 8.00 |
| 10:00 PM – 6:30 AM (overnight) | 30 min | 8 h 30 min | 8 h | 8.00 |
| Split shift: 9:00 AM – 1:00 PM and 2:00 PM – 6:00 PM | (the 1-hour gap) | 9 h | 8 h | 8.00 |
Night shifts that cross midnight
If the end time is smaller than the start time, the shift crossed midnight. Add 24 hours to the end time before you subtract. For 22:00 to 06:30: 06:30 + 24:00 = 30:30. Then 30:30 − 22:00 = 8 h 30 min, minus a 30-minute break = 8 hours.
Split shifts
Work out each part on its own and add them together. 9:00 to 1:00 is 4 hours, 2:00 to 6:00 is 4 hours, so the day is 8 hours. You do not subtract the gap, because you already left it out.
Which breaks should you subtract?
This is where most time cards go wrong. The rules depend on where you work and on your contract, but here is the general picture:
- United States: The US Department of Labor says federal law does not require lunch or coffee breaks. But if your employer gives short breaks of about 5 to 20 minutes, they count as work time and must be paid. A real meal break, usually 30 minutes or more where you are fully relieved of duty, does not count as work time. Some states have their own break laws.
- United Kingdom: If you work more than 6 hours a day, you are entitled to one uninterrupted 20-minute rest break. GOV.UK says that break does not have to be paid; it depends on your contract.
- Everywhere else: Check your contract or local labour rules. As a simple rule for your own time card: subtract the breaks you are not paid for, and keep the ones you are.
This is general information, not legal advice. If you think your breaks or pay are being counted wrongly, check with your employer, HR, or your local labour department.
Minutes to decimal hours cheat sheet
Payroll and invoices use decimal hours, so 7 hours 45 minutes is written as 7.75, not 7.45. Save this chart:
| Minutes | Decimal | Minutes | Decimal |
|---|---|---|---|
| 5 | 0.08 | 35 | 0.58 |
| 10 | 0.17 | 40 | 0.67 |
| 15 | 0.25 | 45 | 0.75 |
| 20 | 0.33 | 50 | 0.83 |
| 25 | 0.42 | 55 | 0.92 |
| 30 | 0.50 | 60 | 1.00 |
Add up a full week in seconds
Doing this by hand for every day gets slow. Our time card calculator does the subtraction, takes off your breaks, adds up the week and shows your pay. In this example, five days of 9:00 to 5:30 with a 30-minute lunch comes to 40 hours, or $800 at $20 an hour.
If your week goes over 40 hours in the US, federal law generally requires overtime at 1.5 times your regular rate for non-exempt employees. The calculator can work that out too.
Calculate your hours now
Enter your start time, end time and break for each day. You get the daily hours, the weekly total and your gross pay, and you can print or download it.
Common time card mistakes
- Writing minutes as decimals. 7 hours 45 minutes is 7.75 hours, not 7.45.
- Forgetting the overnight rule. A shift from 10 PM to 6 AM is 8 hours, not −16.
- Taking off paid breaks. If your short breaks are paid, leave them in.
- Mixing up 12 PM and 12 AM. 12 PM is noon (12:00); 12 AM is midnight (00:00).
- Rounding every day. If you round, follow your employer’s rule and apply it the same way every day.
Quick answers
How do I calculate hours worked with a lunch break?
Subtract your start time from your end time, then subtract the unpaid lunch break. 9:00 AM to 5:30 PM with a 30-minute lunch is 8 hours.
How many hours is 9 to 5 with a 30-minute lunch?
9:00 AM to 5:00 PM is 8 hours. Minus a 30-minute unpaid lunch, that is 7.5 hours.
How do I write 7 hours and 45 minutes in decimal?
Divide 45 by 60 to get 0.75, so it is 7.75 hours.
Is a 30-minute lunch break paid?
Usually not. In the US a real meal break of 30 minutes or more, where you are fully off duty, is generally unpaid, while short breaks of 5 to 20 minutes are paid. Your contract and local law decide in the end.
Confused by 24-hour times?
Turn 17:30 into 5:30 PM (and back) instantly, and print a full 24-hour chart.
Sources: US Department of Labor: breaks and meal periods and GOV.UK: rest breaks at work.
