Time Duration Calculator
Measure the exact time between two moments — across minutes, hours, or days — in one step. Ideal for project tracking, travel planning, and multi-day shifts.
Elapsed time vs. work hours — know the difference
This calculator measures elapsed time: the continuous amount of time between two timestamps. If you start a task Monday at 9:00 AM and finish Friday at 5:00 PM, that is about 104 elapsed hours — but nobody worked 104 hours. For payable time, break the span into shifts and use the work hours calculator instead.
Practical uses for a duration calculator
- Project billing: measure how long a task really took before writing the invoice.
- Travel and logistics: flight windows, road trips, delivery SLAs.
- Event planning: countdowns and run-of-show timing.
- Multi-day shifts: on-call spans and billet rotations where the whole window matters.
Manual method (for spreadsheet users)
In Excel or Google Sheets, subtract the two cells and format the result as time, or multiply by 24 for decimal hours: =(B1−A1)*24 gives elapsed decimal hours. Our hours-to-decimal converter matches that format for single shifts.
Questions people ask
How do I calculate the duration between two dates and times?
Convert both to a common unit (minutes), subtract the start from the end, then break the result into days (÷1440), hours (÷60), and minutes. This calculator does it instantly, including spans across multiple days.
How many hours is 5 days?
Five full days is 120 hours. For a work-week project (Monday 9:00 to Friday 17:30 with nights off), use the calculator above — it measures true elapsed time between the exact timestamps you pick.
What is the difference between elapsed time and work hours?
Elapsed time runs continuously — Monday 9:00 AM to Friday 5:00 PM is about 104 elapsed hours. Work hours only count time actually worked, typically 40 or fewer. Use this tool for elapsed time and the work hours calculator for payable hours.
Does the duration calculator handle overnight spans?
Yes — any end time earlier than the start time within the same day is treated as crossing midnight, and multi-day spans are handled by the date portion automatically.