Project Working Days
Calculator

Inputs

Working days
64.285714

Results

Working days
64.285714
Days off
25.714285
Working weeks
12.857142
Duration in hours
514.285714

Time and date results

Working days64.285714
Days off25.714285
Working weeks12.857142
Duration in hours514.285714

formula-map diagram

Working days
64.285714
Days off
25.714285
Working weeks
12.857142
Duration in hours
514.285714

Time relationship

Formula

working days = calendar days × working days per week ÷ 7

= 64.285714285714

Note

This is a simplified model: it uses fixed conversions (60 minutes per hour, 24 hours per day, 7 days per week, 365 days per year) and ignores leap years, daylight saving changes, public holidays and irregular month lengths. Check the result against a real calendar before relying on it.

More in Time and date

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Frequently asked questions

How does the calculator determine working days for a project?+

It counts the calendar days between the project's start and end dates, then subtracts weekends and any specified holidays to leave only standard business days.

Why use working days instead of calendar days for project planning?+

Work generally doesn't happen on weekends or holidays, so estimating effort or timelines in working days gives a more realistic picture of actual available project time than raw calendar days.

Should company-specific holidays be included?+

Yes, if your organization observes additional non-public holidays (like a company shutdown week), including them gives a more accurate working-day count than using only public holidays.

How is this used to estimate a project deadline?+

If you know the estimated effort in working days, you can add that many working days (skipping weekends and holidays) to the start date to project a realistic completion date.

Does part-time work affect the working-day count?+

The raw count assumes standard full working days; if team members work part-time or split their hours across multiple projects, you'll need to adjust the effective working days separately to reflect their actual availability.