Work hours calculator
With your start time, finish time and break, we work out the effective day and what it adds up to over a week, a month and a year.
Your figures
Result
- Total time on site
- 9 h 00 min
- Hours per week
- 40.00
- Hours per month (average)
- 173.3
- Hours per year
- 2,080
- Hours per day, as a decimal
- 8.00
Summary by period
| Period | Hours |
|---|---|
| horas.alDia | 8.00 |
| A la semana | 40.00 |
| Al mes | 173.33 |
| horas.alAnio | 2,080.00 |
What we assume
- The effective day is the time between start and finish minus the break.
- If the finish time is earlier than the start time it is read as a night shift crossing midnight.
- Monthly and yearly figures are averages over a full year, with no holidays or leave deducted.
How it is calculated
Two subtractions and a multiplication, with one wrinkle: the night shift. If you clock in at 22:00 and out at 06:00, a naive subtraction gives minus sixteen hours. When the finish is before the start, we add a day and get the eight hours you actually worked.
Time on site is not working time
We show both, because they are different numbers and it is worth seeing the gap. Nine hours on site with an hour for lunch is an eight-hour day, and over a year that hour adds up to about 250 hours: six full working weeks.
An example
From 09:00 to 18:00 with a 60 minute break is an 8-hour day, 9 hours on site. Over five days a week that is 40 hours weekly and about 2,088 a year.
Frequently asked questions
Does it handle night shifts?
Yes. Put a finish time earlier than the start time and it reads it as crossing midnight, which is the case a plain subtraction gets spectacularly wrong.
Does the break count as working time?
It depends on your contract and jurisdiction. Enter only the time that does not count; if your break is paid, put 0.
Are holidays deducted from the yearly figure?
No. It is a straight average across the year. Subtract your leave and public holidays for a real figure.
Keep calculating
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Updated on 2026-08-26. Calculations run in your browser; nothing you type is sent to a server.