WFM is workforce management, and in a contact centre or an operations team it names one loop, run over and over: forecast the volume of work, convert that forecast into the number of people who have to be available, build a schedule that puts them there, and then watch the day and react when reality disagrees with the plan. Everything the discipline is famous for (shrinkage, occupancy, adherence, the intraday view) is a component of that loop rather than a separate subject. This page explains what each part decides, what the arithmetic actually depends on, and which parts of the day the plan is obliged to count as paid time whether anybody is on the phones or not. The staffing arithmetic is free on this site: it works your own volumes, handle times and shrinkage rather than anybody's benchmark.
The loop, in the order it runs
Forecast, requirement, schedule, intraday. The forecast says how much work arrives and when, at whatever interval you plan in, usually fifteen or thirty minutes. The requirement converts that into people using the arrival pattern and the average handle time, which is where a queueing model such as Erlang C is used: the relationship between staff and service level is not linear, and adding one person to a small interval moves the answer far more than adding one to a large one. The schedule fits real shifts, breaks and contracts to that requirement, and the intraday view is what happens when Thursday does not read like the forecast. A team that does the first two and skips the last two has produced a number, not a plan.
Shrinkage is the part everyone gets wrong
Shrinkage is the gap between people employed and people available to do the work, and the mistake is treating it as one percentage applied to everything. It is really several different things with different behaviour: holiday and leave, which are planned and known months out; sickness, which is a distribution rather than a number; training and coaching, which are scheduled by somebody else; and the in-day losses of breaks, briefings and system time. Planned and unplanned shrinkage need to be carried separately, because you can move the first and can only absorb the second. A plan that carries one blended figure will be wrong in both directions at once and cannot tell you which.
What the plan is obliged to count as paid time
Some of the day is not on the phones and is still hours worked, which decides both the cost of the plan and how much shrinkage is unavoidable. Rest periods of short duration, running from 5 minutes to about 20 minutes, must be counted as hours worked and cannot be offset against other working time (29 CFR 785.18). Bona fide meal periods are not worktime, but only where the employee is completely relieved from duty, which ordinarily means 30 minutes or more; an agent required to stay at the desk is working while eating (29 CFR 785.19). Waiting while on duty is likewise worktime, whether or not any work arrives (29 CFR 785.15). Orgplanly publishes no legal advice: the point here is that these are inputs to the arithmetic, and a plan that treats paid non-productive time as free is understating both the requirement and the cost.
Occupancy and adherence are constraints, not targets
Occupancy is the share of available time an agent spends actually handling work, and it is an output of how you staffed, not a dial you set. Push it high and average handle time drifts up and attrition follows; let it fall and the plan is paying for idle capacity. Adherence measures whether people were where the schedule said, and its usefulness collapses the moment it is used as a disciplinary score rather than a signal about the schedule's realism. Both belong in the plan as constraints you watch, with the tolerances your own operation can defend. This hub deliberately publishes no industry benchmark for either: the worksheets take your figures, because a number borrowed from somebody else's operation is the fastest way to plan for a business you do not run.
Questions people ask about wfm
Is WFM the same as HR software?
No. An HR system holds the employment record: who works here, on what terms, and what they are paid. WFM decides how many of them are needed at ten past two on Thursday and whether the schedule can deliver it. Some suites sell both, but the two questions are answered by different people using different inputs.
Do small teams need WFM, or is a spreadsheet enough?
A spreadsheet runs a small team well until the arrival pattern gets uneven or the shrinkage stops being predictable. The honest threshold is not headcount but interval: once you have to staff to something finer than a whole day, the arithmetic stops being addition and a spreadsheet starts hiding the error rather than showing it.
What does WFM stand for outside a contact centre?
The same thing. Workforce management is the discipline wherever demand arrives unevenly and staffing has to follow it, which is why retail, hospitality and back-office operations run the identical loop with different words for the volume. The forecasting is what changes; the requirement, schedule and intraday work do not.