Man-hours (person-hours) measure the amount of work in a task, independent of how many people do it. Ten people working eight hours equals 80 person-hours – the same as one person working 80 hours. Project managers use it for estimating and scheduling.
How to use the Man-Hours Calculator
- Number of people
- Hours per person
- Hourly pay
- Working hours per day
Results update as you type, and every field accepts the units shown in its menu.
How it works
Enter the number of people, the hours each works, the hourly pay and the working hours per day.
Tips
- Use figures for the same period (a month, a quarter or a year) for every input so ratios compare like with like.
- Track the metric over time – the trend usually tells you more than a single value.
- Compare your result with industry benchmarks, which vary a lot between sectors.
- Treat the result as a starting point for a decision, then check the assumptions behind each input.
Common mistakes to avoid
- Mixing monthly and yearly numbers in the same calculation.
- Using revenue where the formula needs profit (or the other way round).
- Forgetting hidden costs such as taxes, fees, overheads or your own time.
Inputs explained
| Field | What to enter |
|---|---|
| Number of people | A number |
| Hours per person | A number |
| Hourly pay | Amount in your currency |
| Working hours per day | A number |
What each result means
- Total man-hours = [Number of people]×[Hours per person]
- Cost per person = [Hours per person]×[Hourly pay]
- Total labor cost = [Number of people]×[Hours per person]×[Hourly pay]
- Duration with this crew = [Hours per person]÷[Working hours per day]
Example values
How the main result changes when Number of people changes and everything else stays at the example values above:
| Number of people | Total man-hours |
|---|---|
| 3 | 120 |
| 4.5 | 180 |
| 6 | 240 |
| 7.5 | 300 |
| 9 | 360 |
| 12 | 480 |
Formula
Man-hours = people × hours per personLabor cost = man-hours × hourly payDuration = man-hours ÷ (people × hours per day)Worked example
Inputs — Number of people: 6; Hours per person: 40; Hourly pay: $28; Working hours per day: 8.
Results — Total man-hours = 240; Cost per person = $1,120.00; Total labor cost = $6,720.00; Duration with this crew = 5 working days.
Frequently asked questions
What is a man-hour?
One hour of work by one person – also called a person-hour.
Does adding people always shorten a job?
Not proportionally – coordination overhead grows with team size.
How do I estimate man-hours?
Break the job into tasks and estimate hours per task from past work.
What formula does the Man-Hours Calculator use?
Man-hours = people × hours per person.