How do you calculate timesheet hours?
Subtract the start time from the finish time, take off any unpaid break, convert the minutes to decimal hours, then add the days together and split anything above the ordinary-hours threshold as overtime. Example: 06:00 to 16:30 with a 30-minute unpaid lunch is 10 hours 30 minutes gross, 10.0 hours worked.
- Minutes to decimals — divide by 60 (30 min = 0.5, 45 min = 0.75)
- Night shift — add 24 hours to the finish time before subtracting
- Breaks — deduct unpaid meal breaks, keep paid crib breaks in
- Overtime — apply the weekly and daily limits in the award or agreement
Timesheet calculator with breaks
Enter each day's start and finish times and the unpaid break in minutes. Set your ordinary-hours threshold, hourly rate and overtime multiplier to see total, ordinary and overtime hours plus an indicative gross figure. Everything is calculated in your browser — nothing is submitted or saved.
Indicative only. This calculator applies a single overtime threshold and multiplier — it does not interpret penalty rates, daily overtime steps, shift loadings, site allowances, leave or superannuation. Always check the award or agreement that applies to the worker.
Calculating timesheet hours step by step
Write start and finish in 24-hour time
6:00am to 4:30pm becomes 06:00 to 16:30. Using 24-hour time removes the am/pm mistakes that cause most manual timesheet errors, and it makes night shift easier to handle.
Find the gross duration
Subtract start from finish. 16:30 − 06:00 = 10 hours 30 minutes. If the shift crosses midnight, add 24 hours to the finish time first: 22:00 to 06:00 becomes 30:00 − 22:00 = 8 hours.
Subtract unpaid breaks
Take off any unpaid meal break. 10 hours 30 minutes less a 30-minute unpaid lunch is 10 hours worked. Paid crib or rest breaks stay in the total — check the award or agreement before deciding which is which.
Convert minutes to decimal hours
Divide minutes by 60. 15 minutes = 0.25, 20 = 0.33, 30 = 0.5, 45 = 0.75, 50 = 0.83. Payroll and job costing work in decimals, so 7 hours 45 minutes is 7.75 hours, not 7.45.
Add the days to a weekly total
Total the decimal hours for the week. Round only once, at the end, using your usual rounding rule — rounding every day compounds into hours across a crew over a month.
Split ordinary hours and overtime
Apply the threshold in the award, agreement or contract — commonly 38 ordinary hours a week, and often a daily limit such as 8, 10 or 12 hours as well. Anything above the applicable threshold is overtime at the rate that applies.
Minutes to decimal hours conversion table
Payroll systems and job costing work in decimal hours. This is the table to keep next to the timesheet pile.
| Minutes worked | Decimal hours |
|---|---|
| 5 minutes | 0.08 |
| 10 minutes | 0.17 |
| 15 minutes | 0.25 |
| 20 minutes | 0.33 |
| 25 minutes | 0.42 |
| 30 minutes | 0.50 |
| 35 minutes | 0.58 |
| 40 minutes | 0.67 |
| 45 minutes | 0.75 |
| 50 minutes | 0.83 |
| 55 minutes | 0.92 |
| 60 minutes | 1.00 |
A worked weekly example
A fitter on a 38-hour week, unpaid 30-minute lunch each weekday, plus a Saturday morning callout.
| Day | Start | Finish | Unpaid break | Hours worked |
|---|---|---|---|---|
| Monday | 06:00 | 16:30 | 30 min | 10.00 |
| Tuesday | 06:00 | 17:00 | 30 min | 10.50 |
| Wednesday | 06:00 | 16:00 | 30 min | 9.50 |
| Thursday | 06:00 | 16:30 | 30 min | 10.00 |
| Friday | 06:00 | 14:00 | 30 min | 7.50 |
| Saturday | 07:00 | 12:00 | 0 min | 5.00 |
| Total hours worked | 52.50 | |||
Against a 38-hour ordinary week that is 38.00 ordinary hours and 14.50 overtime hours. Which of those overtime hours attract time-and-a-half, double time, a Saturday penalty or a shift loading depends on the award or agreement — most instruments step the rate after the first two or three hours, and treat weekend work separately again.
Do this, not that
Do this
- Record actual start, finish and break times, not just a total
- Use 24-hour time and decimal hours consistently
- Note which breaks are paid and which are unpaid on the timesheet itself
- Apply one documented rounding rule, at the weekly total only
- Code each block of hours to the job or cost centre it was worked on
- Keep the approved record — Fair Work requires time and wage records for seven years
Avoid this
- Writing 7.45 when you mean 7 hours 45 minutes (that is 7.75)
- Forgetting to add 24 hours when a shift crosses midnight
- Deducting a meal break that was never taken, or that is paid under the award
- Rounding every day in the employer's favour
- Guessing the overtime threshold instead of reading the award or agreement
- Overwriting a worker's submitted hours with no comment or history
The Australian rules that sit behind the maths
The arithmetic is the easy part; the thresholds are not. Full-time ordinary hours are 38 per week under the National Employment Standards , while overtime rates, daily limits, meal breaks and shift loadings come from the modern award or enterprise agreement covering the worker — check it on the Fair Work awards list . Employers must also make and keep time and wage records for seven years under Fair Work record-keeping rules , and long shifts and swing rosters carry fatigue duties under Safe Work Australia guidance . This article explains how to do the calculation — it is not legal or payroll advice for a specific worker.
When to stop calculating by hand
One worker for one week is a two-minute job. Thirty workers across four sites, with unpaid lunches, travel time, site allowances, night shift and Saturday callouts, is a weekly re-entry exercise where every step above can go wrong quietly. That is the point where timesheet software earns its keep: hours captured once on site against a job, breaks and allowances recorded as they happen, award rules applied automatically, and the same approved record feeding payroll, job costing and the client invoice.
