Time Duration Calculator

Add or subtract hours, minutes, and seconds from a start time. Shows resulting time.

How to Use Time Duration Calculator

The Time Duration Calculator is a free online tool that adds or subtracts hours, minutes, and seconds from any start time. Enter your starting time, choose whether to add or subtract, specify the duration, and get the resulting time instantly. The tool handles overflow correctly (wrapping past midnight) and displays results in 24-hour format. Whether you are calculating end times for meetings, figuring out arrival times after travel duration, determining shift end times, or doing any time arithmetic, this tool eliminates manual calculation errors. Perfect for scheduling, time tracking, and planning.

Step-by-Step Instructions

  1. Enter your start time (hours, minutes, seconds)
  2. Choose whether to add or subtract the duration
  3. Enter the duration to add or subtract
  4. View the resulting time and copy it

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