Work Hours Calculator: Calculate Hours Worked Free
Whether you are filling in a timesheet, billing a client, or checking whether your paycheck matches your hours, a work hours calculator removes the mental arithmetic. This guide covers how to calculate hours worked, how to convert to decimal hours, and how to handle breaks, overnight shifts, and split shifts.
How to Calculate Hours Between Two Times
The formula is simple: subtract start time from end time, then subtract unpaid break time.
- Gross hours = End time − Start time
- Net hours worked = Gross hours − Unpaid break
Example: 8:45 AM to 5:15 PM with a 30-minute unpaid lunch. Gross = 8h 30m. Net = 8h 30m − 30m = 8 hours exactly.
How to Use the Hours Calculator
- Open the Hours Calculator.
- Pick a quick-fill preset (8am–5pm, 9am–5pm, etc.) or enter custom start and end times.
- Enter break duration in minutes — only unpaid time; paid breaks stay in.
- For split shifts, click + Add another shift and repeat for each period.
- Read the total in h:mm format and as decimal hours for payroll.
Hours to Decimal Conversion Table
| Minutes | Decimal hours | Example: 8h + minutes |
|---|---|---|
| 0 min | 0.00 | 8.00 hours |
| 15 min | 0.25 | 8.25 hours |
| 20 min | 0.33 | 8.33 hours |
| 30 min | 0.50 | 8.50 hours |
| 40 min | 0.67 | 8.67 hours |
| 45 min | 0.75 | 8.75 hours |
| 50 min | 0.83 | 8.83 hours |
Decimal Hours for Payroll and Invoicing
Payroll systems multiply hours by an hourly rate, which requires decimal hours — not hours and minutes. To convert minutes to decimals, divide minutes by 60. 7h 45m = 7 + (45 ÷ 60) = 7.75 hours. At $28/hr: 7.75 × $28 = $217.00. The calculator shows both formats simultaneously so you can copy the decimal figure directly into a payroll or invoicing tool.
Handling Overnight and Split Shifts
Overnight shifts
If your end time is earlier than your start time, the calculator automatically adds 24 hours to the end time. A shift starting at 10:30 PM and ending at 6:30 AM is correctly calculated as 8 hours — no manual adjustment needed.
Split shifts
A split shift is two or more separate work periods in the same day with an unpaid gap between them — for example, 7am–12pm and 3pm–7pm. Use a separate row for each period rather than entering the whole day as one shift with a long break. The calculator sums all rows correctly: 5h + 4h = 9h total.
Weekly totals
Add one row per day. For a standard 5-day week of 9am–5pm with a 30-minute break each day: 7.5 hours × 5 = 37.5 hours. Add each day individually to account for varying start times, different break lengths, or days off.
Common Timesheet Mistakes
Subtracting paid breaks
Only unpaid time should go in the break field. A paid 10-minute coffee break does not reduce your hours worked — only unpaid lunch breaks or similar unpaid periods do. Check your employment contract if you are unsure which breaks are paid.
Rounding incorrectly
Some employers require rounding to the nearest 15 minutes. 7h 22m rounds down to 7h 15m; 7h 23m rounds up to 7h 30m. The midpoint of each quarter-hour (7, 22, 37, 52 minutes past) determines which way to round. Verify the rounding policy before submitting.
Calculate Work Hours Free
Start and end times, break deduction, multiple shifts, decimal hours for payroll. No signup.
Open Hours Calculator