FTE calculator: work out full-time equivalent

How to calculate FTE

The calculation has one step per person and one step for the team. First decide what a full-time week means in your organisation. In the United States 40 hours is the usual figure, but your own contracts or policies decide it; some employers use 37.5 or 35 hours.

If your contracts state a percentage (for example “80 % position”), that percentage divided by 100 is already the FTE.

Worked example

A team of five works 40, 32, 20, 30 and 16 hours a week, and full time is 40 hours.

Per person that is 40 ÷ 40 = 1.0, 32 ÷ 40 = 0.8, 20 ÷ 40 = 0.5, 30 ÷ 40 = 0.75 and 16 ÷ 40 = 0.4.

The team total is 1.0 + 0.8 + 0.5 + 0.75 + 0.4 = 3.45 FTE. The headcount is 5, and 4 of the 5 people work part-time.

FTE vs headcount

Headcount counts people: every employee is one, whatever their hours. FTE counts capacity: it tells you how many full-time positions those people add up to. The team in the example has a headcount of 5 but only 3.45 FTE.

Both numbers matter, and they answer different questions. Headcount tells you how many people a manager leads, how many laptops, desks or onboarding sessions you need, and how many people a change will affect. FTE tells you how much work the team can take on and what it costs, because salaries usually scale with hours.

On an org chart the gap between the two is often where the surprises are. A department with 12 people can have less capacity than one with 9 if many of the 12 work part-time. Showing both figures per team makes that visible at a glance.

What FTE is used for

FTE turns a list of different contracts into one comparable number. Typical uses:

• Budgeting: personnel costs are planned per position, so budgets are usually set in FTE rather than in people.
• Position planning: an approved headcount plan often says “3.5 FTE” for a team. A vacancy of 0.5 FTE can be filled by one part-time hire or by raising someone’s hours.
• Staffing ratios: ratios such as patients per nurse or students per teacher are normally measured in FTE, so part-time staff are counted fairly.
• Comparing teams: FTE lets you compare the capacity of teams with very different mixes of full-time and part-time staff.
• Reporting: grant applications, annual reports and public bodies often ask for staff numbers in FTE. Check their exact definition, as it can differ from yours.

Common mistakes

Use contracted hours, not hours actually worked in one week, unless you deliberately want to measure overtime. Use the same full-time week for everyone you compare; mixing a 40-hour and a 37.5-hour definition makes totals misleading. And keep unpaid leave, temporary contracts and open positions in mind: decide up front whether they count, then apply that rule consistently.

This calculator does simple arithmetic. It is not legal or tax advice, and laws or programs that count employees (for health insurance, reporting duties or thresholds) may use their own rules.