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Hours & Time Duration Calculator

Calculate the time duration between a start and end time — the hours and minutes worked, minus any break, shown as HH:MM and decimal hours. Ideal for timesheets, payroll and shift planning.

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Quick answer

Hours is a free, private online tool that lets you calculate the hours and minutes between two times, minus breaks. It runs entirely in your browser, so nothing you enter is uploaded to a server.

How to use the Hours

  1. Enter the start time and end time in 24-hour HH:MM format (e.g. 09:00 and 17:30).
  2. Add any break in minutes — it is subtracted from the total.
  3. Read the duration as hours and minutes, decimal hours (for payroll) and total minutes, updated instantly.
  4. Overnight shifts work too: if the end time is before the start, it assumes the next day. Everything runs in your browser.

Privacy: this tool runs entirely in your browser. Your input is never sent to, received by, or stored on any server — there are no uploads and no tracking of what you enter.

About Hours

Working out worked hours

Enter your start and end times (24-hour HH:MM) and a break in minutes; the tool returns the duration in hours and minutes plus decimal hours.

Overnight shifts

If the end time is earlier than the start, the tool assumes the shift crosses midnight and adds 24 hours — so a 22:00–06:00 night shift is counted correctly.

Decimal hours for payroll

Payroll often uses decimal hours (e.g. 8.5 instead of 8h 30m); both are shown, so you can copy whichever your timesheet needs.

Frequently asked questions

How do I calculate the hours between two times?
Enter the start and end time in 24-hour HH:MM format (and any break in minutes). The tool instantly shows the duration as hours and minutes, decimal hours and total minutes.
How many hours is 9 to 5?
9:00 to 17:00 is 8 hours (480 minutes). Subtract a 30-minute break and it's 7 hours 30 minutes, or 7.5 decimal hours.
How do I calculate hours worked with a break?
Enter the break length in minutes — it is subtracted from the total, so a 09:00–17:30 day with a 30-minute break gives 8 hours worked.
What is 8 hours 30 minutes in decimal?
8h 30m is 8.5 decimal hours (30 minutes ÷ 60 = 0.5). The calculator shows both formats automatically.
Does it handle overnight shifts?
Yes — if the end time is before the start time it assumes the shift crosses midnight, so night shifts like 22:00–06:00 are counted correctly.
What time format should I use?
24-hour HH:MM, such as 09:00 or 17:30.

Understanding Hours in depth

What an hours calculator does

An hours calculator works out the time elapsed between a start time and an end time, minus any break, and presents it as hours-and-minutes and as decimal hours. It is the everyday tool for timesheets, shift logging and payroll, removing the awkward base-60 arithmetic of subtracting clock times.

Why time arithmetic is fiddly

Time is base 60, not base 10, so you cannot simply subtract the numbers: 17:30 minus 09:45 is not 7.85 hours. You have to borrow minutes correctly. This tool handles that conversion for you, then also gives the decimal equivalent (7 h 45 m = 7.75 hours), which is what payroll systems usually multiply by an hourly rate.

Handling breaks and overnight shifts

Enter a break in minutes and it is subtracted from the total worked time. The calculator also copes with overnight shifts: if the end time is earlier than the start time, it assumes the shift crossed midnight and adds 24 hours, so a 22:00 to 06:00 shift correctly comes out as 8 hours rather than a negative number.

Decimal hours for payroll

Payroll and invoicing almost always use decimal hours. The conversion is minutes / 60: 15 minutes is 0.25, 30 is 0.5, 45 is 0.75. Getting this right matters - billing 8 hours 30 minutes as 8.30 instead of 8.5 underpays by 12 minutes. The tool shows both forms so there is no ambiguity.

Everyday uses

Total a day's or week's worked hours, log shifts, prepare timesheets, bill clients by the hour, and check that a rota adds up. Use 24-hour HH:MM format for clarity. Everything is calculated locally in your browser.

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