How to Calculate Hours Worked
By the Calculator.hair team · Updated · 7 min read
Short answer
To calculate hours worked, subtract clock-in from clock-out, subtract unpaid breaks, and divide leftover minutes by 60 for decimal hours. A shift from 8:30 AM to 5:15 PM with a 30-minute unpaid lunch is 8 hours 15 minutes, or 8.25 hours. Under the US FLSA, covered nonexempt employees earn at least 1.5 times their regular rate for hours over 40 in a workweek.
Key takeaways
- Hours worked = clock-out − clock-in − unpaid breaks.
- Divide minutes by 60 for payroll: 45 minutes is 0.75 hours, not 0.45.
- Under federal rules, short breaks of about 5 to 20 minutes are paid, and bona fide meal periods of typically 30 minutes or more generally are not.
- FLSA overtime is based on hours over 40 in a single workweek, and hours can't be averaged across weeks.
- Rounding to the nearest quarter hour is accepted only if it doesn't underpay employees over time.
How do you calculate hours worked in a shift?
Subtract the clock-in time from the clock-out time, then subtract any unpaid break. Using a 24-hour clock makes the subtraction easier, so 5:15 PM becomes 17:15.
Worked example: clock in at 8:30 AM, clock out at 5:15 PM, with a 30-minute unpaid lunch. From 8:30 to 17:15 is 8 hours 45 minutes. Taking off the lunch leaves 8 hours 15 minutes, or 8.25 decimal hours.
The time card calculator does this for a full week. Enter one day per line with a label, start time, end time and break, such as "Tuesday, 8:30AM, 5:15PM, 0:30". For a single span with no break, the hours calculator gives the time between two clock times.
How do you convert minutes to decimal hours?
Divide the minutes by 60. Payroll multiplies hours by a pay rate, and that only works with decimals, so 7 hours 45 minutes must become 7.75 hours. Writing it as 7.45 is a common mistake that costs real money: at $20 an hour, 7.75 hours pays $155 and 7.45 hours pays $149.
To convert back, multiply the decimal part by 60: 0.4 hours × 60 = 24 minutes. Values in the table are rounded to two decimal places. Six-minute increments convert exactly to tenths of an hour, which is why some time systems use them.
| Minutes | Decimal hours | Minutes | Decimal hours |
|---|---|---|---|
| 1 | 0.02 | 30 | 0.50 |
| 5 | 0.08 | 35 | 0.58 |
| 6 | 0.10 | 36 | 0.60 |
| 10 | 0.17 | 40 | 0.67 |
| 12 | 0.20 | 42 | 0.70 |
| 15 | 0.25 | 45 | 0.75 |
| 18 | 0.30 | 48 | 0.80 |
| 20 | 0.33 | 50 | 0.83 |
| 24 | 0.40 | 54 | 0.90 |
| 25 | 0.42 | 55 | 0.92 |
Do you subtract breaks from hours worked?
Subtract only unpaid meal periods, not short rest breaks. The US Department of Labor says federal law doesn't require lunch or coffee breaks, but when an employer offers short breaks, usually about 5 to 20 minutes, they count as paid work time and toward overtime.
A bona fide meal period, typically 30 minutes or more, generally isn't work time, provided you are completely relieved from duty. If you eat at your desk while answering calls, that time counts as hours worked and shouldn't be subtracted. Some states have their own break rules, so check your state labor agency as well.
The time card calculator accepts a break as h:mm or as plain minutes, so "0:30" and "30" mean the same thing. Enter only the unpaid time.
How do you calculate hours for an overnight shift?
Add 24 hours to the clock-out time before subtracting. A shift from 10:00 PM to 6:30 AM is 22:00 to 30:30 on that scale, which is 8 hours 30 minutes. With a 30-minute unpaid break, that is 8 hours worked.
Both the time card and hours calculators handle this for you: an end time earlier than the start time is read as the next day. If you enter the full dates and times instead, the second form on the hours calculator works too.
The time card places a whole shift on the line where you enter it. If an overnight shift crosses the start of your employer's workweek, enter the hours before and after that point on separate lines so each part lands in the correct week.
How do you calculate weekly overtime under the FLSA?
Subtract 40 from the total hours in the workweek, then pay those extra hours at no less than 1.5 times the regular rate. This is the standard set by the Fair Labor Standards Act (FLSA), the main US federal wage law, for covered nonexempt employees.
Worked example: an hourly employee earning $20 works the week below. The total is 46 hours, so 40 are regular and 6 are overtime. Regular pay is 40 × $20 = $800, and overtime pay is 6 × $30 = $180, for $980 in gross pay. The time card calculator with payment information turned on and the overtime calculator both return these figures.
| Day | In | Out | Unpaid break | Hours |
|---|---|---|---|---|
| Monday | 8:30 AM | 5:00 PM | 30 minutes | 8.00 |
| Tuesday | 8:30 AM | 5:15 PM | 30 minutes | 8.25 |
| Wednesday | 8:30 AM | 5:00 PM | 30 minutes | 8.00 |
| Thursday | 8:30 AM | 6:00 PM | 30 minutes | 9.00 |
| Friday | 8:30 AM | 5:00 PM | 30 minutes | 8.00 |
| Saturday | 9:00 AM | 1:45 PM | None | 4.75 |
| Total | 46.00 |
A few federal rules are easy to get wrong:
- The workweek is a fixed, recurring 168-hour period, and it can start on any day or hour. It need not be Monday to Sunday.
- Hours can't be averaged across two or more weeks. Working 50 hours one week and 30 the next still means 10 overtime hours in the first week.
- The FLSA doesn't require extra pay for weekends, holidays or regular days of rest as such. Saturday in the example above is paid at a premium only because the week passed 40 hours.
- The regular rate can be higher than the hourly wage, because it includes most pay for employment. Discretionary bonuses and expense reimbursements are among the exclusions.
- Exempt employees aren't covered by this overtime requirement, and state rules can be stricter. Some states also set daily overtime rules, so check with your state labor department.
The time card calculator adds up everything you enter as one week when it applies weekly overtime, so enter one workweek at a time. Its overtime options also include a per-day threshold for states with daily overtime rules. The overtime calculator expects regular and overtime hours as separate entries, so split them first. Both report gross pay before taxes. For the next steps, see how to calculate take-home pay and converting hourly pay to salary.
How does 15-minute time clock rounding work?
Each punch moves to the nearest quarter hour: 1 to 7 minutes past a quarter hour rounds down, and 8 to 14 minutes rounds up. This is sometimes called the 7-minute rule, though that name is informal.
Federal regulation 29 CFR 785.48(b) describes rounding to the nearest 5 minutes, tenth of an hour or quarter hour. It accepts the practice for enforcement only if it doesn't, over time, leave employees underpaid for the hours they actually worked. A system that always rounds in the employer's favor doesn't meet that test. State rules may also apply.
The time card calculator's Round Time setting rounds each start and end time to the nearest interval before adding the hours. The table shows how two similar days can move in opposite directions, each with a 30-minute unpaid break. Here the differences cancel out, but that balance isn't guaranteed in practice, so compare rounded and actual totals periodically.
| Actual punches | Actual hours | Rounded punches | Rounded hours | Difference |
|---|---|---|---|---|
| 8:07 AM to 5:08 PM | 8 h 31 min (8.52) | 8:00 AM to 5:15 PM | 8 h 45 min (8.75) | +14 min |
| 8:08 AM to 5:07 PM | 8 h 29 min (8.48) | 8:15 AM to 5:00 PM | 8 h 15 min (8.25) | −14 min |
Calculators in this guide
Frequently asked questions
How do I calculate my hours worked for the week?
Work out each day as clock-out minus clock-in minus unpaid breaks, convert to decimals, and add the days. The time card calculator totals a full week from one line per day.
How do I calculate 7 hours and 30 minutes on a time card?
Divide the minutes by 60 and add them to the hours: 30 ÷ 60 = 0.5, so the entry is 7.5 hours.
Is a 30-minute lunch break paid?
Under federal rules, it generally isn't paid if you are completely relieved from duty for a bona fide meal. If you have to work while eating, the time counts as hours worked.
Is 15-minute rounding legal?
Federal rules accept rounding to the nearest quarter hour if it doesn't, over time, leave employees underpaid for time actually worked. State law may add limits, so check your state as well.
Do I get overtime for working more than 8 hours in a day?
Federal law bases overtime on hours over 40 in a workweek, not on daily hours. Some states also have daily overtime rules, so check with your state labor department.
How is time and a half calculated?
Multiply the regular rate by 1.5, then by the overtime hours. At $20 an hour, the overtime rate is $30, so 6 overtime hours pay $180.