WhenMathRequired Weekly Hours Calculator
Give an effort total and a window, and find the weekly hours it takes, or give a weekly rate and solve for the target date or the effort it supports.
Worked example
80 hours of effort spread across a 4-week window, January 4 to February 1, 2027, needs exactly 20 hours a week to finish on time. Shrink that same window to 2 weeks instead, keeping the effort fixed at 80 hours, and the required weekly rate doubles to 40 hours a week, since the identical amount of work now needs to fit into half the time.
Common mistakes
- Confusing calendar weeks with working weeks. This measures plain 7-day calendar weeks between two dates, not working weeks with holidays already removed.
- Assuming weekly availability stays even across the whole window. This produces one flat weekly rate, without accounting for any specific week being lighter or heavier than the others.
Limitations
Weeks are counted as continuous 7-day spans, not aligned to any particular weekday. It does not account for uneven weekly availability, so a week with known reduced capacity needs to be planned around separately.
Frequently asked questions
- Can available weeks be fractional?
- Yes, a window of 10 days works out to 1.43 weeks, and the weekly-hours answer reflects that exact fraction rather than rounding to a whole week first.
- Does this account for holidays or reduced availability during the window?
- No, it measures plain continuous 7-day calendar weeks between two dates, with no adjustment for holidays, vacations, or any other reduced availability during that span.