CalcWhenWork Hours Calculator
Working 9:00 AM to 5:00 PM with a 30-minute break, 5 days a week is 37.5 hours per week — about 1,950 hours a year.
How it works
Contracts and job ads love to mix units — hourly rate here, annual salary there, a 37.5-hour week somewhere else. This tool takes one normal day of your schedule and scales it honestly: hours per day, per week, per month and per year, with pay at each step if you add a rate.
Monthly hours use the true average (a year has 52 weeks spread over 12 months), so the figures reconcile: weekly × 52 = yearly, and monthly = yearly ÷ 12.
The method
Net day = (end − start, +24h if overnight) − break. Week = net day × days per week. Year = week × 52; month = year ÷ 12. Holidays and vacation are not deducted — the panel shows contracted time, and you can lower the days-per-week figure to model part-time patterns.
Frequently asked questions
Why is a month not just 4 weeks?
Because 12 months of 4 weeks would only make 48 weeks — a month is on average 4.33 weeks. Using week × 52 ÷ 12 keeps the monthly and yearly figures consistent with each other.
Should breaks be counted?
Unpaid breaks should not, which is why the break is subtracted. If your breaks are paid, set the break to 0.
Does it include holidays and vacation?
No. It shows the full contracted schedule. To model a four-day week or a term-time pattern, change the days per week.