Work Hours Calculator
Add up shifts with breaks to get your hours worked, split into regular and overtime.
What this tool does
A work hours calculator adds up shift times with unpaid breaks to give daily and weekly hours worked, separating regular hours from overtime against a configurable threshold. Enter clock-in and clock-out for each shift and the break length, and it returns the payable hours per day, the weekly total, and the overtime above the threshold - in both hours-and-minutes and decimal form, which is what timesheets and payroll systems actually use.
Adds up shift times with unpaid breaks to give daily and weekly hours worked.
Separates regular hours from overtime using a configurable weekly threshold.
Totals a multi-day week, so the timesheet adds up before it is submitted.
Converts hours and minutes to decimal hours for payroll entry.
How to use it
- Enter the clock-in and clock-out times for each shift.
- Enter the unpaid break for that shift, if any.
- Set the weekly overtime threshold, such as 40 hours.
- Add shifts until the week is complete.
- Read the daily hours, the weekly total and the overtime.
Why use this calculator
Adding up shift times with unpaid breaks to give daily and weekly hours removes the arithmetic errors that a timesheet quietly turns into money. The two classic mistakes are counting a break as paid time and converting minutes wrong: a shift of 08:30 to 17:15 with a 30-minute break is 8.25 hours, not 8.5, and a payroll system entered as 8.5 pays for fifteen minutes that were not worked. The decimal conversion is where the errors live.
Why we built it
We built the work hours calculator to show decimal hours next to clock hours, because that is the format payroll systems expect and the place errors hide. The overtime-pay-calculator values the overtime hours this produces, the salary-calculator converts the totals into periods, and the time-duration-calculator handles the raw addition and subtraction of durations. For the pay itself, the freelance-rate-calculator works the equivalent from the other side.
The date-difference-calculator covers the date side when a shift crosses midnight, and the online-stopwatch times a shift as it happens.
Who this tool is for
- Employees filling in a weekly timesheet
- Shift workers with varying start and end times
- Managers checking a submitted timesheet
- Freelancers and contractors logging billable hours
When to use it
- At the end of each week, before submitting a timesheet.
- When checking whether a shift crossed into overtime.
- Converting hours and minutes into decimal hours for payroll.
- Verifying a payslip that looks slightly wrong.
How it is calculated
Shift hours = (clock-out − clock-in) − break. Convert to decimal by dividing the minutes by 60. Weekly hours = the sum of the daily figures. Overtime = the amount above the weekly threshold. A shift crossing midnight counts the part before midnight and the part after: 22:00 to 06:00 with no break is 8 hours.
Worked example: 08:30 to 17:15 with a 30-minute break is 8h 45m of clock time less 30 minutes = 8h 15m, or 8.25 decimal hours. Five such shifts total 41.25 hours - which at a 40-hour threshold is 1.25 hours of overtime.
Decimal hours convert minutes by dividing by 60: 15 minutes is 0.25, 30 is 0.5, 45 is 0.75. The quarter-hour fractions are exact in decimal, which is why 15-minute timesheet increments are standard.
Common shift patterns
| Shift | Break | Payable | Decimal |
|---|---|---|---|
| 09:00 – 17:00 | None | 8h 00m | 8.00 |
| 09:00 – 17:30 | 30 min | 8h 00m | 8.00 |
| 08:30 – 17:15 | 30 min | 8h 15m | 8.25 |
| 07:00 – 15:30 | 30 min | 8h 00m | 8.00 |
| 22:00 – 06:00 | None | 8h 00m | 8.00 |
| 10:00 – 19:00 | 45 min | 8h 15m | 8.25 |
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Shift | Times | Break |
|---|---|---|
| Monday | 08:30 – 17:15 | 30 min |
| Tuesday | 08:30 – 17:15 | 30 min |
| Wednesday | 08:30 – 17:15 | 30 min |
| Thursday | 08:30 – 17:15 | 30 min |
| Friday | 08:30 – 17:15 | 30 min |
| Overtime threshold | 40 hours |
With those inputs, the calculator returns:
- Each day: 8h 15m, or 8.25 decimal hours
- Weekly total: 41h 15m, or 41.25 decimal hours
- Regular hours: 40.00
- Overtime: 1.25 hours
Where timesheets go wrong
The errors are almost always small and consistent, which is exactly how they survive a glance. A break not deducted, minutes rounded the wrong way, or a night shift counted as short - each is a few minutes a day and a meaningful amount a year. Checking the decimal figure against the hours-and-minutes figure catches the conversion errors.
| Error | Effect | Check |
|---|---|---|
| Break not deducted | Overstates by the break each day. | Compare clock span with payable hours. |
| Minutes entered as hours | 15 min entered as 1.25 instead of 0.25. | Sanity-check the decimal against the span. |
| Night shift split wrong | Counts only the part after midnight. | Include the pre-midnight hours. |
| Rounding up each shift | Inflates the week by minutes. | Round once at the week's total, not per shift. |
What you enter, and what you get back
| Item | Details |
|---|---|
| Shift times | Clock-in and clock-out for each day. |
| Break | Unpaid minutes deducted from each shift. |
| Overtime threshold | Weekly hours above which time is overtime. |
| Result | Daily hours, weekly total, decimal hours and overtime. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| Total slightly under the payslip | Payslip counts the break or rounds differently. | Check the employer's rounding convention. |
| Night shift looks too short | Times crossing midnight counted as same-day. | Enter it as a crossing shift; the calculator handles it. |
| Overtime zero at 39h 45m | Threshold is 40 and rounding is down. | Confirm whether the employer rounds to quarter hours. |
| Decimal looks wrong | Minutes misread as a fraction of 100. | Divide minutes by 60, not 100 — 30 min is 0.5. |
Assumptions and limitations
- Assumes each shift is a single span; split shifts need to be entered as separate rows.
- Does not model break rules, rest periods or daily overtime thresholds.
- Rounding conventions vary by employer; check whether yours rounds per shift or weekly.
- Overtime rates and multipliers are valued by the overtime pay calculator, not here.
Frequently asked questions
How do I calculate hours worked from clock times?
Subtract the clock-in time from the clock-out time, then deduct the unpaid break. A shift from 08:30 to 17:15 spans 8 hours 45 minutes; with a 30-minute break the payable time is 8 hours 15 minutes. For shifts crossing midnight, count the hours before midnight and after as one continuous span.
How do I subtract a break from hours worked?
Take the clock span and deduct the break minutes from it. 8h 45m less a 30-minute break is 8h 15m, or 8.25 decimal hours. Deduct the break from the span, not from the finish time, unless your employer's convention is to shift the end time instead.
How do I calculate weekly work hours?
Add the payable hours of every shift in the week. Five shifts of 8h 15m total 41h 15m, or 41.25 decimal hours. Convert each shift to decimal first so the addition is exact: 15 minutes is 0.25, 30 is 0.5, 45 is 0.75.
How do I calculate overtime hours?
Subtract the overtime threshold from the weekly total, when the total exceeds the threshold. At a 40-hour threshold, a 41.25-hour week carries 1.25 hours of overtime. If the week falls below the threshold, there is no overtime. The overtime pay calculator then applies the multiplier to those hours.
How do I convert hours and minutes to decimal hours?
Divide the minutes by 60 and add the hours: 8h 15m becomes 8 + 15 ÷ 60 = 8.25. Quarter hours convert exactly — 0.25, 0.5 and 0.75 — which is why timesheets use 15-minute increments. Never divide minutes by 100: that turns 30 minutes into 0.3 instead of 0.5.
How do I add up a timesheet for the week?
Enter each shift with its times and break, and let the calculator total the days. Check the weekly decimal figure against the hours-and-minutes total, since the mismatch is where conversion errors show. Compare the overtime figure with what the payslip claims before submitting.