Time Duration Calculator

What is the Time Duration Calculator?

Calculate the duration between two clock times, including overnight shifts. Calculating the time between two clock times handles overnight shifts and unpaid breaks, which are easy to miscount by hand.

How to use the Time Duration Calculator

1. Enter your start time, your end time, your unpaid break.
2. Results update automatically as you type; you can also press Calculate.
3. Read the output: duration, decimal hours, total minutes.
4. Use the 📊 chart to see the result visually, then copy or share it.

Formula and method

Worked example

With start time = 09:15, end time = 17:45, unpaid break = 30 minutes, the Time Duration Calculator returns duration: 8:00 (h:mm); decimal hours: 8.00; total minutes: 480.

Where the Time Duration Calculator helps in real life

You worked from 10 p.m. to 6:30 a.m. with a 30-minute unpaid break. The calculator handles the shift crossing midnight and gives eight paid hours.

You are tracking time on a freelance project across several sessions in a day. Calculating each duration and adding them up gives an accurate total for your invoice.

Common mistakes to avoid

• Forgetting to add 24 hours when a shift crosses midnight.
• Including unpaid breaks in paid time.
• Mixing up a.m. and p.m. on overnight shifts.
• Rounding minutes differently from one shift to the next.

💡 Practical tip: When the end time is earlier than the start time, the shift crossed midnight — add 24 hours.

Tips for better results

• Use 24-hour time to avoid a.m./p.m. confusion.
• Record breaks separately from shift start and end times.
• Convert the result to decimal hours for payroll.

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