Hours Calculator
Add, subtract, or calculate the duration between times. Convert between decimal hours and hours:minutes:seconds format. Perfect for timesheets and payroll.
Result
Time
10:15:00
Calculator Mode
Times to Add
Time 1
Time 2
Result
Time Format
10:15:00
10 hours, 15 minutes, 0 seconds
Decimal Hours
10.2500
Rounded: 10.25 hours
Decimal ↔ Time Reference
0.25
15 min
0.50
30 min
0.75
45 min
1.00
1 hour
1.25
1:15
1.50
1:30
1.75
1:45
2.00
2 hours
Common Work Schedule Calculations
| Schedule | Hours/Day | Hours/Week | Decimal/Day |
|---|---|---|---|
| Standard (9-5) | 8:00 | 40:00 | 8.0 |
| With 30min lunch | 7:30 | 37:30 | 7.5 |
| With 1hr lunch | 7:00 | 35:00 | 7.0 |
| Part-time (6hrs) | 6:00 | 30:00 | 6.0 |
| Extended (10hrs) | 10:00 | 40:00 | 10.0 |
Quick Answer
To calculate hours between times: subtract start from end time. From 9:00 AM to 5:30 PM = 8 hours 30 minutes = 8.5 decimal hours. To convert minutes to decimal: divide by 60 (30 min = 0.5 hours). For overnight shifts, add 24 hours if end time is smaller than start. Work week: 40 hours standard, overtime usually kicks in after 8 hours/day or 40 hours/week.
Key Facts
- Standard work week: 40 hours (8 hours/day x 5 days)
- Convert minutes to decimal hours: divide by 60 (30 min = 0.5)
- Overtime typically begins after 8 hours/day or 40 hours/week
- Federal overtime rate: 1.5x regular pay
- Lunch breaks are usually unpaid (30-60 minutes)
- Annual work hours: approximately 2,080 (40 hrs x 52 weeks)
- 24-hour time: add 12 to PM hours (5 PM = 17:00)
- For overnight shifts: end time + 24 hours - start time
Frequently Asked Questions
To add times, convert everything to the same unit (usually minutes), add them together, then convert back. For example, 2:45 + 1:30 = (165 + 90) minutes = 255 minutes = 4:15.
Decimal time represents hours as a decimal number instead of hours:minutes. For example, 1.5 hours = 1 hour 30 minutes. It's commonly used in payroll, billing, and timesheets because it's easier to calculate with.
Divide minutes by 60. For example, 45 minutes = 45/60 = 0.75 hours. Common conversions: 15 min = 0.25, 30 min = 0.5, 45 min = 0.75. For 2 hours 15 minutes: 2 + (15/60) = 2.25 hours.
Use "Time Between" mode. Enter your start time and end time. The calculator will show the duration. For overnight shifts, it automatically accounts for crossing midnight. Remember to subtract breaks!
When the end time is before the start time (like 10 PM to 6 AM), the calculator assumes the end time is the next day and adds 24 hours automatically. The result shows the actual duration.
Military (24-hour) time runs from 00:00 to 23:59 without AM/PM. Convert PM times by adding 12 (1 PM = 13:00). This calculator accepts both formats but displays in 24-hour format internally.
Result
Time
10:15:00