Resource Capacity Calculator
Calculate Resource Capacity step by step: Capacity = people × (working days − leave) × hours per day × availability %.
In short
Formula: Capacity = people × (working days − leave) × hours per day × availability %.
What this calculator does
Calculate Resource Capacity step by step: Capacity = people × (working days − leave) × hours per day × availability %. Worked example, questions and limitations included.
Use it to turn People, Working days in period, Hours per day, Leave and holidays per person, and the other shown inputs into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this project estimation calculation.
Inputs and what they mean
- People
- — number value.
- Working days in period
- — number value.
- Hours per day
- — number value.
- Leave and holidays per person
- — number value.
- Share of time available for project work
- — number value.
How to use it
- Enter each value in the unit shown next to the box (use the unit converter first if your numbers are in other units).
- Check the breakdown to see every intermediate step.
- Read the limitations before relying on the result.
Formula
Standard resource capacity planning arithmetic.
Availability covers support duties, other projects and admin; you choose it.
Enter leave as an average per person if it differs between people.
Capacity = people × (working days − leave) × hours per day × availability %.
Inputs used: People, Working days in period, Hours per day, Leave and holidays per person, Share of time available for project work.
Worked example
5 people for a 20-day month
- 5 × 18 × 8 = 720 h.
- 720 × 0.75 = 540 h.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Averages across people.
- Ignores skills; hours are not interchangeable.
- Does not model ramp-up.
- Results are planning estimates built only from the figures you enter. They are not a guarantee of cost, schedule or delivery, and they do not replace your organisation's own project controls.
- The result depends on the values you enter for this resource capacity calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Common questions
What availability should I use?
Measure it from timesheets. There is no universal figure; it varies by role and organisation.
Should part-timers count as one person?
Enter them as a fraction (e.g. 0.5) in the people box.
Is this the same as utilization?
No. Capacity is hours available; utilization is the share actually used. See the utilization rate calculator.
How do I use the Resource Capacity Calculator?
Enter the required values for People, Working days in period, Hours per day, Leave and holidays per person, Share of time available for project work. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the Resource Capacity Calculator use?
Capacity = people × (working days − leave) × hours per day × availability %. The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.
Can the Resource Capacity Calculator be used for exact decisions?
Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.
Related tools
Calculate Project Labor Estimate step by step: Direct hours = items × hours per item.
Calculate Project Duration Estimate step by step: PERT: E = (O + 4M + P) ÷ 6, σ = (P − O) ÷ 6.
Calculate Team Size step by step: FTE = total effort ÷ (duration × project hours per person per week).
Calculate Project Budget step by step: Cost baseline = direct costs + contingency reserve.
Calculate Project Contingency step by step: Percentage: contingency = base × %.
Calculate Project Profit step by step: Markup: price = cost × (1 + markup).