Free Work Hours Calculator
Calculate exactly how many hours and minutes you worked between a start time and an end time, with optional break deduction and a weekly total across up to 7 days.
Quick answer
A work hours calculator takes a start time and end time, subtracts any unpaid break, and returns the exact hours and minutes worked. For example, clocking in at 9:00 AM and out at 5:30 PM with a 30-minute break gives 8 hours worked. You can add up to seven daily entries to get a weekly total. All calculations run in the browser and no time data is stored.
Formula & method
Daily hours worked
Hours Worked = (End Time β Start Time) β Break Duration
- End Time β Clock-out time in hours and minutes
- Start Time β Clock-in time in hours and minutes
- Break Duration β Total unpaid break time in minutes
If the shift crosses midnight (end time is earlier than start time), 24 hours are added to the end time before subtracting.
Weekly total
Weekly Hours = Ξ£ (Daily Hours Worked for each day)
- Ξ£ β Sum of all daily worked hours across the week
Days left blank (no start or end time) are skipped and do not count as zero.
Examples
- Input
- Start 9:00 AM, End 5:30 PM, Break 30 min
- Result
- 8 hours 0 minutes
- Why
- 9:00 AM to 5:30 PM spans 8 hours 30 minutes. Subtracting the 30-minute lunch break leaves exactly 8 hours 0 minutes worked.
- Input
- Start 10:00 PM, End 6:30 AM, Break 45 min
- Result
- 7 hours 45 minutes
- Why
- 10:00 PM to 6:30 AM spans 8 hours 30 minutes (the calculator adds 24 hours to the end time because the shift crosses midnight). Subtracting 45 minutes gives 7 hours 45 minutes worked.
- Input
- Each day: Start 8:00 AM, End 4:30 PM, Break 0 min Γ 5 days
- Result
- 42 hours 30 minutes
- Why
- Each shift is 8 hours 30 minutes. Five such shifts total 5 Γ 8.5 = 42.5 hours, which is 42 hours 30 minutes.
- Input
- Start 7:45 AM, End 7:00 PM, Break 60 min
- Result
- 10 hours 15 minutes (8 h regular + 2 h 15 min overtime)
- Why
- 7:45 AM to 7:00 PM spans 11 hours 15 minutes. Subtracting the 1-hour break leaves 10 hours 15 minutes worked. The first 8 hours are regular time; the remaining 2 hours 15 minutes exceed the standard 8-hour threshold and count as overtime.
When to use this tool
- Calculating pay for hourly workers before running payroll.
- Verifying time-sheet totals against a schedule.
- Tracking weekly overtime by summing daily shift lengths.
Common mistakes
- Forgetting to subtract break time, which inflates the hours worked.
- Not accounting for midnight crossover β if your shift ends on the next calendar day, the end time is earlier than the start time and 24 hours must be added.
- Entering times in the wrong order without a midnight flag, producing a negative duration.
Frequently asked questions
How do I calculate hours worked between two times?
Subtract the start time from the end time to get the raw duration, then subtract any unpaid break time. The result is your hours worked. For example, 9:00 AM to 5:30 PM with a 30-minute break is (8 h 30 min) β 30 min = 8 hours.
How does the calculator handle shifts that cross midnight?
If the end time is earlier on the clock than the start time, the calculator automatically adds 24 hours to the end time. For example, starting at 10:00 PM and ending at 6:00 AM is treated as 8 hours, not a negative number.
Can I calculate my weekly total hours?
Yes. Add entries for each working day and the tool sums all valid daily totals into a weekly hours and minutes figure at the bottom.
How is overtime calculated?
The calculator shows overtime as any daily hours worked beyond 8 hours. For example, if you work 10 hours 15 minutes in a day, 8 hours are regular and 2 hours 15 minutes are overtime. Note that actual overtime rules vary by country, state, and employer.
Is my time data saved or sent to a server?
No. All calculations run entirely in your browser. Your start times, end times, and break durations are never uploaded or stored.
What if I work the same hours every day β do I have to enter them separately?
Currently each day is entered individually so you can handle different schedules, breaks, or days off. For identical shifts you can enter them in sequence quickly, and the weekly total updates automatically.
Sources & references
- U.S. Department of Labor β Hours Worked Under the FLSA
- IRS Publication 15 β Employer's Tax Guide (payroll time rules)
External references open in a new tab. We are independent and not affiliated with these organizations.
- β Free to use
- β No sign-up required
- β Runs entirely in your browser β nothing is uploaded.
- β Formula and method shown above
Provided βas isβ for general information only β results may be inaccurate, so verify before you rely on them. No warranty; use at your own risk.
Built and reviewed by HIFreeTools against the formula shown above and any authoritative references cited on this page. See our methodology and editorial standards.
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