Calculator
FTE Calculator
Build a bottom-up staffing model from the actual work your team does. Pick roles from a 72-role library across 7 functions, define each task's frequency, duration and complexity, and get a defensible full-time-equivalent headcount — adjusted for leave, shrinkage and your industry's productivity reality.
Size any team from the work it does
The FTE Calculator builds a staffing number from the ground up — from the actual work a team does, not from gut feel or last year's headcount plus a bit. You assemble the roles, describe the tasks each one performs with their frequency, duration and complexity, and the tool converts that workload into annual hours and then into a defensible full-time-equivalent figure, adjusted for leave, holidays, shrinkage and the productivity reality of your industry. The result is a headcount you can actually justify.
From your inputs to a result you can act on
Pick from a library of seventy-two roles across seven functions, or adapt them to your context. The roles frame the work; you decide which apply to the team you are sizing.
For each task, set how often it happens, how long it takes and how complex it is. This task-level detail is what makes the output bottom-up and defensible rather than a top-down guess.
The calculator nets out annual leave, public holidays and shrinkage — meetings, training, admin, the unavoidable friction of real work — and applies industry productivity and staffing factors so the number reflects reality.
You receive a full-time-equivalent headcount with the workload and assumptions that produced it, ready to save, share and defend in a resourcing conversation.
What it does
Headcount decisions are among the most consequential and least rigorous that organisations make. Teams are frequently sized by precedent, by whoever argues hardest, or by a blunt ratio borrowed from elsewhere — and the result is chronic over- or under-staffing that nobody can explain. The FTE Calculator replaces that guesswork with a transparent, workload-driven model: it starts from the tasks that must be done and works forward to the number of people required to do them.
The critical move is translating work into hours. A task that takes twenty minutes and happens fifty times a day is a very different staffing demand from one that takes two hours but happens weekly, yet intuition routinely misjudges which is heavier. By capturing frequency, duration and complexity for each task, the tool accumulates a genuine annual workload — and only then converts it into people, so the headcount rests on evidence rather than assertion.
The approach behind it
A full-time equivalent is not simply a warm body; it is a unit of available productive capacity, and treating those as the same is the most common error in staffing. A person on the payroll is not available every working hour: they take leave, public holidays fall through the year, and a meaningful share of every day disappears into meetings, training, breaks and administration. The calculator models this explicitly through leave, holiday and shrinkage adjustments, so the FTE figure reflects capacity that can actually be deployed on the work.
On top of that, it applies industry productivity and staffing factors, because the same nominal workload demands different resourcing in different sectors. Regulated, high-assurance environments carry overhead that a lighter-touch operation does not, and a credible model has to account for that rather than pretend all hours are equal. Renascence encoded these factors from workforce-planning practice so the output is calibrated, not generic.
The philosophy throughout is defensibility. Every number traces back to a stated assumption about the work, which means the output is not a verdict to be accepted or rejected but a model to be examined and adjusted. When a finance partner or operations leader questions the figure, you can walk them straight to the task and assumption behind it — which is exactly how resourcing decisions should be made.
How it helps you
The clearest benefit is winning — or defending — headcount with evidence. Whether you are arguing for additional resource or protecting a team from cuts, a bottom-up model built from actual work is far more persuasive than an assertion that you are busy. It reframes the conversation around workload rather than opinion.
It is equally valuable for planning growth and change. Because the model is driven by tasks, you can test scenarios: what happens to required FTE if volume doubles, if a process is automated, or if a new service line is added. That turns staffing from an annual guess into a living plan you can flex as the business changes.
Finally, it exposes hidden imbalance. Building the model often reveals that a team is stretched not because it is understaffed overall but because work is distributed poorly, or that a high-frequency micro-task is quietly consuming a role's entire capacity. Those insights are frequently more valuable than the headline number itself.
Who it is for
It is built for operations and workforce-planning leaders sizing or restructuring teams, for managers making the case for resource, for consultants delivering operating-model or efficiency work, and for finance partners who want a rational basis for headcount rather than a negotiated one.
It suits both a quick estimate and a detailed submission. You can sketch a team in minutes with the role library, or invest in granular task modelling when the decision — and the scrutiny — warrants it.
Frequently asked
Shrinkage is the portion of paid time not spent on core work — meetings, training, breaks, admin and the like. Ignoring it is the single biggest cause of understaffing, so the calculator nets it out explicitly.
Yes. Because the model is workload-driven, you can change volumes, tasks or roles and immediately see the effect on required FTE — ideal for planning growth, automation or restructuring.
No. The seventy-two-role library is a starting frame across seven functions; you select and adapt what fits the team you are actually sizing.
Ready when you are
Open FTE Calculator
No setup required — start now and save your work to the portal.