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  3. Time Duration Calculator

Time Duration Calculator

Calculate time between two times, add or subtract durations. Convert hours, minutes, and seconds easily.

Duration Result

Duration

8h 30m

8.50 total hours

Total Hours8.50
Total Minutes510.0
Total Seconds30,600

Calculation Type

Start Time

09:00:00

End Time

17:30:00

Duration Breakdown

0

Weeks

0

Days

8

Hours

30

Minutes

0

Seconds

All Conversions

UnitValue
Weeks0.0506
Days0.3542
Hours8.5000
Minutes510.00
Seconds30,600

Quick Reference

1 Hour

3,600 seconds

1 Day

86,400 seconds

1 Week

604,800 seconds

Work Day (8h)

28,800 seconds

Frequently Asked Questions

Convert both times to a common unit (seconds or minutes), then subtract the earlier from the later. For times crossing midnight, add 24 hours (86400 seconds) to the end time if it's smaller than the start time.

Convert to seconds, subtract. Add 24h if crossing midnight.

1 hour = 3,600 seconds (60 × 60). 1 day = 86,400 seconds (24 × 3,600). 1 week = 604,800 seconds (7 × 86,400). These conversions are useful for time calculations.

Hour: 3,600. Day: 86,400. Week: 604,800 seconds.

Add each unit separately (hours + hours, minutes + minutes, etc.), then carry over: if minutes ≥ 60, subtract 60 and add 1 to hours. Same for seconds to minutes, hours to days.

Add each unit, carry over: 60 seconds→1 minute, 60 minutes→1 hour.

Elapsed time is the actual time that has passed between two points. Duration is a length of time that may or may not be anchored to specific start/end points. Both are measured the same way.

Elapsed: between two points. Duration: a length of time. Measured the same.

Multiply the decimal part by 60 to get minutes. Example: 2.75 hours = 2 hours + (0.75 × 60) minutes = 2 hours 45 minutes. For seconds, multiply the decimal minutes by 60.

Decimal × 60 = minutes. 2.75h = 2h 45m (0.75 × 60 = 45).

Duration Result

Duration

8h 30m

8.50 total hours

Total Hours8.50
Total Minutes510.0
Total Seconds30,600