Hours Calculator – Work Hours, Breaks, Overtime & Pay

Hours Calculator

Hours worked = end time − start time − unpaid breaks, so a 9:00 AM to 5:30 PM shift with a 30-minute lunch is 8 hours (8.00 in decimal), or 40 hours over five days, which pays $1,000 a week at $25 an hour. Hours over 40 a week can be paid at 1.5× overtime.

By the Calculators With Steps team · Updated November 10, 2026 · How we check our math

How to use the hours calculator

Enter the start time and end time of a shift. If the end time is earlier than the start, the calculator treats it as an overnight shift that ends the next day.
Enter your unpaid break in minutes, such as a 30-minute lunch. Leave it at 0 if breaks are paid.
Set the days worked per week to get weekly hours. Half days are allowed, such as 4.5.
Optionally add your hourly rate and choose the currency. Leave the overtime box ticked to apply time and a half above 40 hours a week.

You get hours per shift in h:mm and decimal form, weekly hours, pay per shift, weekly pay, a 52-week yearly estimate and any overtime hours.

How work hours are calculated

Hours worked = (end time − start time) − unpaid break

When the shift crosses midnight, add 24 hours to the end time first. To turn the answer into decimal hours for a time card, divide the minutes by 60:

Decimal hours = whole hours + minutes ÷ 60

Weekly hours are the daily hours multiplied by the days worked. Pay is hours multiplied by the hourly rate, with any hours above 40 in the week paid at 1.5 times the rate.

Worked examples

Shift	Break	Hours worked	Decimal
9:00 AM – 5:30 PM	30 min	8 h 00 min	8.00
8:45 AM – 5:15 PM	45 min	7 h 45 min	7.75
10:00 PM – 6:30 AM (overnight)	30 min	8 h 00 min	8.00
7:00 AM – 5:30 PM	30 min	10 h 00 min	10.00

A full week at $25 an hour. Five shifts of 9:00 AM to 5:30 PM with a 30-minute lunch is 8.00 hours a day and 40.00 hours a week. There is no overtime, so weekly pay is 40 × $25 = $1,000, or $52,000 over 52 weeks.

Quarter-hour times at $18.50. 8:45 AM to 5:15 PM is 8 hours 30 minutes. After a 45-minute break that is 7 hours 45 minutes, or 7.75 hours. Each shift pays 7.75 × $18.50 = $143.38, and five shifts make 38.75 hours and $716.88 a week.

Overtime and time and a half

The US Fair Labor Standards Act (FLSA) requires covered, non-exempt employees to be paid at least one and a half times their regular rate for every hour over 40 in a workweek. The rule is weekly. Long single days do not trigger federal overtime, and weekends or holidays don’t either unless the weekly total goes past 40.

Take a worker on $20 an hour who works 8:00 AM to 5:00 PM with a 30-minute break, six days a week:

Item	Hours	Rate	Pay
Regular time	40.00	$20.00	$800.00
Overtime	11.00	$30.00	$330.00
Total	51.00		$1,130.00

Without overtime the same 51 hours would pay $1,020, so time and a half adds $110 a week. Some states add daily overtime or double time, and salaried exempt staff are not covered, so check your state labor office and your contract. To see what lands in your bank account after taxes, use the paycheck calculator.

Breaks: paid or unpaid?

Under the federal rules in Department of Labor Fact Sheet 22, rest periods of about 20 minutes or less are counted as hours worked and must be paid. Bona fide meal periods, typically 30 minutes or more, generally do not need to be paid, as long as you are fully relieved from duty. If you eat at your desk while answering calls, that time counts as work. Enter only unpaid break time in the calculator.

Decimal hours quick reference

Minutes	6	15	20	30	45	50
Decimal hours	0.10	0.25	0.33	0.50	0.75	0.83

Tips for accurate time cards

Record times as they happen. Federal rules allow employers to round punches to the nearest 5 minutes, tenth of an hour or quarter hour, but only if the rounding evens out over time.
Keep the break column honest. A 15-minute paid rest break should not be deducted.
For adding up odd durations, such as several short tasks, the time calculator adds hours, minutes and seconds directly.
To turn an hourly rate into an annual figure and back, try the salary calculator.

Hours Calculator: frequently asked questions

How do I calculate hours worked?

Subtract the start time from the end time, then take off any unpaid break. 9:00 AM to 5:30 PM is 8 hours 30 minutes, and after a 30-minute lunch that leaves 8 hours, or 8.00 decimal hours.

How do I convert hours and minutes to decimal hours?

Divide the minutes by 60 and add them to the hours. 7 hours 45 minutes is 7 + 45 ÷ 60 = 7.75 hours. Writing it as 7.45 is a common payroll mistake that loses 18 minutes.

How do I calculate hours for an overnight shift?

If the end time is earlier than the start time, add 24 hours to the end time before subtracting. 10:00 PM to 6:30 AM is 8 hours 30 minutes, or 8 hours after a 30-minute break. The calculator does this for you.

How many hours is 9 to 5?

9:00 AM to 5:00 PM is 8 hours. With a 30-minute unpaid lunch it is 7.5 hours a day, or 37.5 hours over a five-day week.

How is overtime calculated?

Under the federal Fair Labor Standards Act, non-exempt employees must get at least 1.5 times their regular rate for hours over 40 in a workweek. Working 8:00 AM to 5:00 PM with a 30-minute break for six days is 51 hours, so at $20 an hour the pay is 40 × $20 + 11 × $30 = $1,130.

Are lunch breaks paid?

Under federal rules, short rest breaks of about 20 minutes or less count as paid work time. A bona fide meal period, usually 30 minutes or more, does not have to be paid if you are completely relieved from duty. Some states have their own break laws.

Can my employer round my clock-in times?

Federal rules accept rounding start and stop times to the nearest 5 minutes, tenth of an hour or quarter hour, as long as it averages out over time and you are paid for all the time you actually work.