Hours Worked Formula Explained, With Examples
Every hours worked result comes from one formula. Once you understand what goes into it, you can sanity-check any figure you are given, whether by an employer, a bank, a teacher or another website.
The formula
Hours = out − in − break.
What each input means
- Clock in: the value you enter in the calculator.
- Clock out: the value you enter in the calculator.
- Unpaid break (minutes): the value you enter in the calculator.
Example
For example, with these inputs:
- Clock in: 08:30
- Clock out: 17:45
- Unpaid break (minutes): 60
the calculator returns:
- Hours worked: 8 h 15 min
- Decimal hours: 8.25 hours
How the result changes
The table keeps the other inputs at their example values and changes unpaid break (minutes).
| Unpaid break (minutes) | Hours worked | Decimal hours |
|---|---|---|
| 08:30 | 8 h 15 min | 8.25 hours |
| 30 | 8 h 45 min | 8.75 hours |
| 45 | 8 h 30 min | 8.50 hours |
| 75 | 8 h 00 min | 8.00 hours |
| 90 | 7 h 45 min | 7.75 hours |
Why it matters
Dates and durations matter for notice periods, leave planning, project deadlines and contracts. Counting days on a calendar is slow and easy to get wrong, especially across months of different lengths.
When sharing dates internationally, write the month as a word to avoid confusion between day-month and month-day formats.
The Gregorian calendar has months of 28 to 31 days and adds a leap day almost every four years, which makes counting days by hand surprisingly error-prone. Converting dates to day numbers and subtracting avoids the problem.
Singapore has 11 gazetted public holidays a year, and when one falls on a Sunday the following Monday is a holiday. Working-day calculations therefore need holidays removed separately from weekends.
Related calculations
- Add Days to a Date Calculator: Finds the date a number of days after another date.
- Subtract Days from a Date Calculator: Finds the date a number of days before another date.
- Working Days Calculator: Counts weekdays between two dates, inclusive.
- Day of the Week Calculator: Tells you which weekday any date falls on.
Use the Hours Worked Calculator to plug in your own numbers.
Run your own numbers: Hours Worked Calculator