How to Calculate Work Hours Between Two Times
The Basic Formula
The simplest way to calculate work hours is:
Convert everything to minutes first, then divide by 60 at the end.
Step-by-Step: Calculate Manually
Step 1 — Convert both times to minutes from midnight
Multiply hours by 60 and add the minutes.
Example: 9:30 AM = (9 × 60) + 30 = 570 minutes
Example: 5:45 PM = (17 × 60) + 45 = 1,065 minutes
Step 2 — Subtract start from end
1,065 − 570 = 495 minutes
Step 3 — Deduct break time
With a 45-minute lunch break: 495 − 45 = 450 minutes
Step 4 — Convert to hours
450 ÷ 60 = 7.5 hours (7 hours 30 minutes)
Common Examples
| Start | End | Break | Work Hours |
|---|---|---|---|
| 9:00 AM | 5:00 PM | 1 hour | 7.0 hours |
| 8:30 AM | 5:30 PM | 30 min | 8.5 hours |
| 10:00 AM | 6:30 PM | 45 min | 7.75 hours |
| 7:00 AM | 3:00 PM | 30 min | 7.5 hours |
| 11:00 PM | 7:00 AM | 30 min | 7.5 hours (night) |
How to Calculate Work Hours in Excel
Basic formula:
Where B2 = start time, C2 = end time. Multiply by 24 to convert Excel's fraction to hours.
With break deduction:
For overnight shifts:
Decimal Hours Quick Reference
| Minutes | Decimal |
|---|---|
| 15 min | 0.25 |
| 30 min | 0.50 |
| 45 min | 0.75 |
| 20 min | 0.33 |
| 40 min | 0.67 |
⏱ Calculate Work Hours Instantly
Enter start time, end time, and break — get your hours in seconds. Handles night shifts automatically.
Open Work Hours Calculator →Frequently Asked Questions
How do I calculate hours if I cross midnight?
Add 24 hours to your end time before subtracting. Start at 10 PM (22:00), finish at 6 AM (6:00) → 30:00 − 22:00 = 8 hours. Our calculator handles this automatically.
How do I convert 7 hours 45 minutes to decimal?
Divide minutes by 60 and add to hours: 45 ÷ 60 = 0.75. So 7h 45m = 7.75 decimal hours.
What is the difference between work hours and clock hours?
Clock hours is total time between start and end. Work hours deducts unpaid breaks. Most employers pay for work hours only.