Calculate hours, minutes, and seconds between two times instantly. Perfect for work hours, payroll, project tracking, and scheduling. 100% Free & Accurate.
Enter start and end times to calculate the exact duration
Get accurate time duration results in seconds. No manual math required - just enter times and get instant answers.
Automatically handles times that cross midnight. Perfect for night shift workers and 24-hour operations.
Converts time to decimal hours automatically. Multiply by hourly rate for instant pay calculations.
Works perfectly on all devices - smartphones, tablets, and desktops. Calculate anywhere, anytime.
Precision time calculations verified against international time standards. Trusted by thousands daily.
No registration, no hidden fees, no limits. Use our time duration calculator as many times as you need.
Accurately track employee work hours by calculating the duration between clock-in and clock-out times. The decimal hours format makes it easy to multiply by hourly rates for precise payroll calculations. Perfect for HR departments, small businesses, and freelancers tracking billable hours.
Monitor how much time you spend on specific projects or tasks. Calculate total duration between project start and completion to improve time management, estimate future projects accurately, and bill clients properly for time-based services.
Easily calculate hours for employees working night shifts that cross midnight. For example, calculate duration from 11:00 PM to 7:00 AM to get exactly 8 hours - our calculator automatically handles the date transition.
Calculate travel duration for trips, commutes, or journey planning. Know exactly how long your travel will take by entering departure and arrival times, helping you schedule meetings and appointments more effectively.
Plan events, meetings, or conferences by calculating exact duration. Ensure proper time allocation for each segment and avoid scheduling conflicts by knowing precise time spans.
Students can track study session duration to monitor productivity, set goals, and ensure balanced study schedules across different subjects. Calculate total study time per day, week, or month.
Calculate work hours with break time subtraction. If you work 9 AM to 5 PM with a 1-hour lunch break, calculate 9 AM to 12 PM (3 hours) plus 1 PM to 5 PM (4 hours) for total work time of 7 hours.
Track workout duration, running time, or exercise sessions. Monitor rest periods between sets or intervals to optimize training schedules and track fitness progress over time.
Time duration calculation measures the amount of time between two specific points. Whether you're calculating work hours between 9 AM and 5 PM, or determining how long a project took from start to finish, understanding time duration is essential for accurate time management and payroll processing.
While our online calculator makes this instant, understanding the manual process helps you verify results and understand the logic:
Step 1: Convert to 24-Hour Format
Convert all times to 24-hour format (military time) to avoid AM/PM confusion. In 24-hour format, 1 PM becomes 13:00, 2 PM becomes 14:00, and so on. AM hours remain the same (9 AM = 09:00).
Step 2: Calculate Hour Difference
Subtract the start hour from the end hour. For example, if calculating 9:00 AM (09:00) to 5:00 PM (17:00), subtract: 17 - 9 = 8 hours.
Step 3: Calculate Minute Difference
If the end time has fewer minutes than the start time, borrow 60 minutes from the hour and add to the end minutes. Then subtract start minutes from end minutes.
Step 4: Handle Midnight Crossing
For times crossing midnight (like 11 PM to 7 AM), add 24 hours to the end time before subtracting. Example: 23:00 to 07:00 becomes 23:00 to 31:00, which equals 8 hours.
Decimal hours simplify payroll calculations. To convert minutes to decimal hours, divide minutes by 60:
• 15 minutes = 0.25 hours
• 30 minutes = 0.50 hours
• 45 minutes = 0.75 hours
• 8 hours 30 minutes = 8.5 decimal hours
For payroll, multiply decimal hours by hourly rate. If someone earns $20/hour and works 8.5 hours, their gross pay is $20 × 8.5 = $170.
The 12-hour clock uses numbers 1-12 with AM (ante meridiem = before noon) and PM (post meridiem = after noon) designations. Midnight is 12:00 AM and noon is 12:00 PM.
The 24-hour clock (military time) uses hours 00-23 without AM/PM. It's the international standard for avoiding ambiguity: 00:00 is midnight, 12:00 is noon, 13:00 is 1 PM, and 23:59 is one minute before midnight.
Standard 9-to-5 Workday:
From 9:00 AM to 5:00 PM = 8 hours exactly. This is the most common full-time work schedule.
With Lunch Break:
9:00 AM to 5:00 PM with 1-hour lunch = 7 working hours. Calculate 9 AM to 12 PM (3 hours) + 1 PM to 5 PM (4 hours).
Night Shift:
11:00 PM to 7:00 AM = 8 hours. The calculator automatically handles the midnight crossover.
Part-Time Shift:
2:00 PM to 6:30 PM = 4 hours 30 minutes = 4.5 decimal hours.
Our calculator also handles time duration spanning multiple days. This is crucial for:
• Project deadline calculations
• Vacation time tracking
• Service level agreement (SLA) monitoring
• Construction project labor hours
• Medical shift coverage planning
When calculating across dates, the calculator considers complete 24-hour periods plus any partial hours. For example, from Monday 2:00 PM to Wednesday 10:00 AM includes 2 full days plus partial hours.
1. Use consistent time formats - Choose either 12-hour or 24-hour format and stick with it
2. Account for breaks - Calculate work time separately before and after breaks
3. Round appropriately - Many businesses round to 15-minute intervals (quarter hours)
4. Document everything - Keep records of all time calculations for payroll verification
5. Verify overnight shifts - Double-check calculations that cross midnight
Healthcare: Calculate nurse shift hours, patient care time, surgery duration, and medical procedure time tracking for billing and compliance.
Construction: Track labor hours per project, equipment usage time, and contractor billable hours for accurate job costing and invoicing.
Transportation: Monitor driver hours for DOT compliance, calculate delivery time windows, and track fleet vehicle usage for logistics optimization.
Retail: Schedule employee shifts, calculate overtime hours, track store operating hours, and manage seasonal staffing needs.
Freelancing: Bill clients accurately by tracking project hours, calculate effective hourly rates, and monitor time spent on different clients.
Education: Track student study hours, calculate class duration, monitor exam time allocation, and schedule academic activities.
Using an online time duration calculator offers significant advantages over manual calculations:
• Speed: Instant results versus several minutes of manual calculation
• Accuracy: Eliminates human error in complex calculations
• Convenience: Available 24/7 on any device with internet access
• Multiple formats: Get results in hours, minutes, seconds, and decimal format simultaneously
• No learning curve: Intuitive interface requires no special training
Split Shifts: Calculate multiple work periods in one day. For split shifts like 6 AM-10 AM and 2 PM-6 PM, calculate each segment separately (4 hours + 4 hours = 8 hours total).
Flexible Hours: For employees with varying schedules, use the calculator to track each work session and sum the totals for accurate weekly or monthly hours.
International Time Zones: When calculating duration across time zones, convert all times to a single time zone first, then calculate the duration.
Overtime Calculation: Calculate total hours worked, then subtract 40 hours to determine overtime hours (in US contexts). Overtime typically pays 1.5× regular rate.
To calculate time duration, enter your start time (hours, minutes, seconds, and AM/PM) and end time in the calculator above. Click "Calculate Duration" and the tool will instantly show you the exact time difference in multiple formats including total hours, minutes, seconds, and decimal hours for payroll.
Yes! Our time duration calculator automatically detects when a time period crosses midnight and calculates the correct duration. For example, entering 11:00 PM as start time and 7:00 AM as end time will correctly show 8 hours duration. This feature is essential for night shift workers, security personnel, and 24-hour operations.
Enter your clock-in time and clock-out time into the calculator. The result shows both standard hours:minutes format and decimal hours. Use the decimal hours for payroll calculations - simply multiply decimal hours by your hourly wage rate. For example, 8.5 hours × $20/hour = $170 gross pay.
A 12-hour clock uses hours 1-12 with AM (before noon) and PM (after noon) designations. A 24-hour clock (also called military time) uses hours 00-23 without AM/PM. For example, 2:00 PM in 12-hour format is 14:00 in 24-hour format. Our calculator accepts both formats for your convenience.
Yes! Use the date input fields along with time inputs to calculate the exact duration between two dates and times. This feature is perfect for project deadlines, vacation time tracking, multi-day event planning, and long-term time period calculations. The calculator shows total duration including days, hours, minutes, and seconds.
To convert minutes to decimal hours, divide minutes by 60. Our calculator does this automatically, but here are common conversions: 15 minutes = 0.25 hours, 30 minutes = 0.50 hours, 45 minutes = 0.75 hours. For example, 8 hours 30 minutes equals 8.5 decimal hours, which is useful for payroll systems.
Yes, completely free! There are no hidden charges, no registration required, and no usage limits. Use our time duration calculator as many times as you need for personal or business purposes. We believe essential tools like time calculators should be accessible to everyone at no cost.
Our time duration calculator provides 100% accurate results down to the second. The calculation algorithm has been tested against international time standards and is used by thousands of users daily for critical applications like payroll processing, project management, and compliance reporting.
Absolutely! Our time duration calculator is fully optimized for mobile devices including smartphones and tablets. The responsive design ensures easy input on touchscreens, and all features work perfectly on iOS and Android devices. Calculate time duration anywhere, anytime.
For work hours with breaks, calculate the time periods before and after the break separately, then add them together. For example, if working 9 AM to 5 PM with a 1-hour lunch at 12 PM: Calculate 9 AM to 12 PM (3 hours) and 1 PM to 5 PM (4 hours), totaling 7 working hours. This ensures accurate payroll calculations.
Decimal hours simplify payroll calculations, billing, and time reporting. Instead of working with hours and minutes separately, decimal format expresses time as a single number. This makes it easy to multiply by hourly rates, sum multiple time entries, and integrate with payroll software. Most modern time tracking systems use decimal hours.
Yes! Project managers use our time duration calculator to track task duration, calculate project timelines, monitor milestone deadlines, and estimate resource allocation. Calculate the exact time between project start and completion to improve future estimates and maintain accurate project documentation.