Time duration & hours calculator

About this time duration calculator

Working out hours between two clock times gets awkward with half-hours, lunch breaks and shifts that end after midnight. This calculator does it instantly and gives the result both as hours and minutes and as decimal hours, which is the format most payroll and timesheet systems need.

If the end time is earlier than the start time, it assumes the shift ran past midnight. Add an hourly rate to see what the time is worth.

How to use the Time Duration Calculator

1. Enter the start time and end time.
2. Enter any unpaid break in minutes.
3. Optionally add an hourly rate.
4. Read the duration, decimal hours and pay.

Converting minutes to decimal hours

Decimal hours = total minutes ÷ 60

So 15 minutes = 0.25 h, 30 minutes = 0.5 h and 45 minutes = 0.75 h. A shift of 8 hours 30 minutes is 8.5 decimal hours, not 8.30.

Worked example

A shift from 9:00 AM to 5:30 PM with a 30-minute unpaid lunch is 8 hours (8.00 decimal hours). A night shift from 10:00 PM to 6:30 AM with a 30-minute break is also 8 hours.

Tips for better results

• Round consistently — many employers round to the nearest quarter hour; check your policy.
• To add up a whole week, total the decimal hours from each day.

Frequently asked questions

Last reviewed: October 2026 · Results are calculated in your browser.