How to use the hours calculator
- Enter your schedule: For each day you worked, fill in the start time, end time and break minutes. Use 24-hour format (09:00, 13:30, 22:00). Leave days blank if you did not work.
- Set overtime rules: Adjust the weekly overtime threshold (default 40 hours) and the overtime pay multiplier (default 1.5x).
- Read the results: The table shows each day's hours in HH:MM and decimal, the weekly total, regular hours, overtime hours and the multiplier. This hours calculator updates live as you type.
How the hours are calculated
For each day the calculator parses the start and end times as minutes since midnight. If the end time is earlier than or equal to the start time it assumes the shift crosses midnight and adds 24 hours. The daily minutes equal the elapsed minutes (end minus start, plus 1,440 when the shift crosses midnight) minus the break minutes. A 09:00 to 17:00 shift with a 30-minute break gives (1020 - 540) - 30 = 450 minutes, which is 7 hours 30 minutes or 7.50 decimal hours.
Weekly totals sum the daily minutes. Regular hours are the lesser of the weekly total and the overtime threshold. Overtime hours are the weekly total minus regular hours (zero if negative). The overtime multiplier is shown for reference but does not change the hour counts.
Common work-week patterns
The table below shows typical schedules and their weekly hour totals before overtime.
| Pattern | Daily hours | Days | Weekly total |
|---|---|---|---|
| Standard 9-5 with 30 min lunch | 7.5 | 5 | 37.5 |
| 9-5 with 1 hour lunch | 7.0 | 5 | 35.0 |
| Four 10-hour days (7-5:30, 30 min break) | 10.0 | 4 | 40.0 |
| Three 12-hour shifts (7-7, 1 hr break) | 11.0 | 3 | 33.0 |
| Night shift 10 PM - 6 AM (45 min break) | 7.25 | 5 | 36.25 |
When to use decimal vs HH:MM
Decimal hours (7.50) are convenient for payroll spreadsheets because they multiply directly by an hourly rate. HH:MM (7:30) is easier to read on a printed timesheet. This hours calculator shows both side by side so you can copy whichever format your system expects.
To convert manually: divide minutes by 60. For example 7 hours 45 minutes = 7 + 45/60 = 7.75. Decimal hours are rounded to two places for display; the totals themselves are kept in whole minutes, so rounding never accumulates across the week.
Overtime rules vary by jurisdiction
In the United States the Fair Labor Standards Act sets the federal overtime threshold at 40 hours per week at 1.5x the regular rate. Some states have daily overtime (e.g., California after 8 hours in a day) or higher multipliers. This tool uses a single weekly threshold and multiplier; for daily overtime rules you would need to calculate each day separately and sum the overtime portions.
If your workplace uses a different threshold or a different multiplier (2x on holidays), adjust the two fields at the bottom of the form.
Common mistakes to avoid
- Forgetting breaks: Unpaid meal breaks must be subtracted. A 30-minute lunch every day saves 2.5 hours per week.
- Midnight crossover: Enter 22:00 to 06:00 for a night shift, not 22:00 to 30:00.
- 12-hour format: The calculator expects 24-hour times. 9:00 AM is 09:00; 9:00 PM is 21:00.
- Empty vs zero: Leave a day completely blank if you did not work. Entering 00:00 to 00:00 with no break counts as 24 hours.
Worked examples
| Example | Input | Result |
|---|---|---|
| Standard 40-hour week | Mon start: 09:00; Mon end: 17:00; Mon break (min): 30; Tue start: 09:00; Tue end: 17:00; Tue break (min): 30; Wed start: 09:00; Wed end: 17:00; Wed break (min): 30; Thu start: 09:00; Thu end: 17:00; Thu break (min): 30; Fri start: 09:00; Fri end: 17:00; Fri break (min): 30; Weekly overtime threshold (hours): 40 | Mon: 7:30 (7.50); Tue: 7:30 (7.50); Wed: 7:30 (7.50); Thu: 7:30 (7.50); Fri: 7:30 (7.50); Weekly total: 37:30 (37.50); Regular hours: 37:30 (37.50); Overtime hours: 0:00 (0.00); Overtime multiplier: 1.50x |
| Four 10-hour days | Mon start: 07:00; Mon end: 17:30; Mon break (min): 30; Tue start: 07:00; Tue end: 17:30; Tue break (min): 30; Wed start: 07:00; Wed end: 17:30; Wed break (min): 30; Thu start: 07:00; Thu end: 17:30; Thu break (min): 30; Weekly overtime threshold (hours): 40 | Mon: 10:00 (10.00); Tue: 10:00 (10.00); Wed: 10:00 (10.00); Thu: 10:00 (10.00); Weekly total: 40:00 (40.00); Regular hours: 40:00 (40.00); Overtime hours: 0:00 (0.00); Overtime multiplier: 1.50x |
| Shift with overnight | Mon start: 22:00; Mon end: 06:00; Mon break (min): 45; Tue start: 22:00; Tue end: 06:00; Tue break (min): 45; Wed start: 22:00; Wed end: 06:00; Wed break (min): 45; Weekly overtime threshold (hours): 40 | Mon: 7:15 (7.25); Tue: 7:15 (7.25); Wed: 7:15 (7.25); Weekly total: 21:45 (21.75); Regular hours: 21:45 (21.75); Overtime hours: 0:00 (0.00); Overtime multiplier: 1.50x |
| Part-time three days | Mon start: 10:00; Mon end: 14:00; Mon break (min): 0; Wed start: 10:00; Wed end: 14:00; Wed break (min): 0; Fri start: 10:00; Fri end: 14:00; Fri break (min): 0; Weekly overtime threshold (hours): 40 | Mon: 4:00 (4.00); Wed: 4:00 (4.00); Fri: 4:00 (4.00); Weekly total: 12:00 (12.00); Regular hours: 12:00 (12.00); Overtime hours: 0:00 (0.00); Overtime multiplier: 1.50x |
FAQ
Does this hours calculator handle daily overtime rules like California's 8-hour threshold?
No. It applies a single weekly threshold. For daily overtime you would calculate each day's overtime separately and add them up.
Can I use 12-hour time with AM/PM?
The input fields expect 24-hour format (09:00, 21:30). Convert 9:00 AM to 09:00 and 9:00 PM to 21:00 before entering.
What happens if my shift crosses midnight?
Enter the start time (e.g., 22:00) and the end time (e.g., 06:00). The calculator detects that the end is earlier than the start and adds 24 hours automatically.
How are decimal hours rounded?
Decimal hours are rounded to two decimal places for display. Totals are kept in whole minutes, so rounding error never builds up across the week.
Can I calculate bi-weekly or monthly totals?
This tool calculates one week at a time. Run it for each week and add the weekly totals together for a longer period.
Does the overtime multiplier affect the hour counts?
No. The multiplier is shown for reference only. Regular and overtime hours are counted in hours; the multiplier is used later when you compute pay.
Is my data sent to a server?
No. All calculations run in your browser. Nothing is uploaded or stored.