Time Duration Calculator
Calculate the exact duration between two times in hours, minutes, and seconds.
Time Duration Calculator
Calculate the exact duration between two times in hours, minutes, and seconds.
Date Difference Formula
ℹ️ Weeks = days ÷ 7 | Months ≈ days ÷ 30.44 | Years ≈ days ÷ 365.25
Disclaimer
Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.
Frequently Asked Questions
Pro Tips
Business days vs calendar days matter for deadlines. A 30-day contract deadline is 30 calendar days, but a "30 business day" deadline is closer to 6 weeks.
Leap years (every 4 years, except century years not divisible by 400) add 1 day. Long-term date calculations that span February should account for this.
For countdown timers to important dates, include time zones — "Friday midnight" in New York is 3 hours different from California.
Age in years alone hides important milestones. "30 years, 6 months" is much more precise than "30 years old" for medical or legal calculations that need exact age.
When to Use This Calculator
Calculate exact days between today and a project deadline to plan work backwards.
Find exact age in days, weeks, or months for birthday milestones or official age verification.
Calculate days until a trip or visa expiry, or find the length of a journey between dates.
Verify contract end dates, notice periods, or lease expiry dates down to the exact day.
Count down days in a 30-day, 60-day, or 90-day fitness or habit challenge.
About the Time Duration Calculator
This time duration calculator computes the precise elapsed time between any two points in time — whether they are clock times on the same day or full date-time values spanning days, weeks, or years. Enter a start date-time and an end date-time to see the duration expressed in years, months, days, hours, minutes, and seconds simultaneously. Built for project timelines, event planning, legal deadline tracking, and anyone measuring the exact gap between two moments.
How to Use the Time Duration Calculator
- 1
Enter the start date and time (the earlier point in time).
- 2
Enter the end date and time (the later point in time).
- 3
See the duration expressed in all units: years, months, days, hours, minutes, seconds.
- 4
See the total duration in a single unit (e.g. total hours or total minutes) for calculations.
- 5
Switch the start and end to calculate how long until a future event.
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Calculate total hours and minutes between start and end times for any shift.
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Count the number of days until or since any date — countdown or up.
Days Between Dates
Calculate days, weeks, months, and years between two dates. Business days option.
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