ShiftPlumHow to calculate monthly work hours from your shifts
To calculate work hours for a month, add the elapsed minutes of the relevant shifts, subtract unpaid breaks and divide by 60. The difficult part is usually choosing the right events: a repeating pattern, an overnight shift or an old filter can change the total.
Define the period before counting
Choose the first and last dates of the period you want to review. A calendar month and an employer's reporting period may have different boundaries. Write down which calendar and event category you are including, especially if you keep personal appointments alongside work.
Separate planned hours from a record of what happened. A future schedule shows expected hours. For a retrospective total, update each changed start, finish and unpaid break from your own records. Marking an event complete is not a clock-in system.
Work in minutes until the final total
Suppose you have ten shifts from 08:00 to 16:00, each with a 30-minute unpaid break, and four shifts from 20:00 to 08:00 the next day, each with a 45-minute unpaid break. Assume there is no clock change during these shifts.
| Shifts | Minutes per shift after breaks | Total |
|---|---|---|
| 10 day shifts | 480 − 30 = 450 | 4,500 minutes |
| 4 night shifts | 720 − 45 = 675 | 2,700 minutes |
| 14 shifts combined | 4,500 + 2,700 | 7,200 minutes = 120 hours |
Use the correct rule at the month boundary
ShiftPlum selects events by their starting date. A shift starting on 30 November at 20:00 and ending on 1 December at 08:00 is included in the November date range as a whole. It is not automatically split at midnight for monthly statistics or export.
If your external report allocates hours to the calendar day on which they occurred, reconcile that boundary separately. Keep the original start and end times, and allocate any break to the correct part from your records. Do not invent a midnight split for a break whose timing you do not know.
Set the Statistics filters deliberately
Open Statistics, select the dates and calendar, then choose Work when you want work shifts only. Clear any lingering calendar search and make sure the relevant calendars are visible. Review the detailed rows, not just the large total.
Check the first and last rows, unusually short or long shifts, and any day with two similar events. A timed personal appointment can contribute time when all categories are included. Choose the category that answers your question instead of assuming that every recorded hour is a work hour.
Explain differences before changing the numbers
Common causes of a mismatch are a missed shift, a duplicate, a break entered twice, a wrong overnight end day or a different reporting period. A calendar time zone also matters when clocks change. Compare one event at a time until you find the cause.
An estimate of earnings adds another layer: saved rates, fixed payments, per-event overtime settings and deductions. Matching a duration does not establish that a pay estimate matches payroll. Keep currencies separate and use the employer's records for any payroll reconciliation.
Keep an inspectable monthly record
Once the dates and rows are right, export the calendar and period to CSV. Preserve that original file and make adjustments in a separate working copy. Record the reporting dates in the filename so an old export is not mistaken for an updated one.
For a readable summary, print the filtered Statistics view to PDF. Recheck the preview before saving it. A file is a snapshot: if you later correct a shift, produce a new export and make clear which version is current.