Time Duration Calculator

Calculate the duration between two times, two dates, or a combination of both. Find out exactly how many hours, minutes, and seconds are between any two points in time.

Duration:
8 hours 30 minutes
From 9:00 AM to 5:30 PM
0
Days
8
Hours
510
Total Minutes
30,600
Total Seconds
0
Weeks
8.5
Decimal Hours

Common Time Durations

Duration Minutes Hours Decimal Hours
15 minutes150h 15m0.25
30 minutes300h 30m0.5
45 minutes450h 45m0.75
1 hour601h 0m1.0
1.5 hours901h 30m1.5
2 hours1202h 0m2.0
4 hours2404h 0m4.0
8 hours (workday)4808h 0m8.0
24 hours (1 day)1,44024h 0m24.0

How to Calculate Time Duration

Time duration is the amount of time that passes between two points. This calculator helps you find the exact duration in various units - from seconds to weeks - making it useful for tracking work hours, calculating event lengths, and more.

Three Calculation Modes

This calculator offers three modes to suit different needs:

  • Times Only: Calculate duration between two times on the same day (e.g., 9:00 AM to 5:30 PM)
  • Dates Only: Calculate the number of days between two dates
  • Dates & Times: Precise calculation including both date and time components
Duration Formula:

Duration = End Time - Start Time

Total Minutes = (Hours x 60) + Minutes
Total Seconds = (Hours x 3600) + (Minutes x 60) + Seconds
Decimal Hours = Total Minutes / 60

Understanding Decimal Hours

Decimal hours express time as a decimal number rather than hours and minutes:

  • Payroll Systems: Many timekeeping systems use decimal hours
  • Project Billing: Easier to multiply by hourly rates
  • Scientific Applications: Simpler for calculations
Quick Conversion: To convert minutes to decimal, divide by 60.
15 min = 0.25 hrs | 30 min = 0.5 hrs | 45 min = 0.75 hrs

Common Use Cases

  • Work Hours: Calculate total hours worked for timesheets
  • Event Planning: Determine event duration for scheduling
  • Travel Time: Calculate journey duration
  • Cooking: Track total cooking and prep time
  • Exercise: Log workout duration
  • Meetings: Track meeting length for productivity

Handling Overnight Durations

When the end time is earlier than the start time (crossing midnight), the calculator assumes the end time is on the following day:

  • 10:00 PM to 2:00 AM = 4 hours
  • 11:30 PM to 6:00 AM = 6 hours 30 minutes
Pro Tip: For work hour tracking, use "Dates & Times" mode if your work crosses midnight or spans multiple days for accurate calculation of overnight shifts.