Occupancy calculator
Occupancy is the share of an agent's logged-in time spent handling contacts. Enter the contacts in an interval, their handle time and the agents you have staffed, and the calculator gives the occupancy that implies, the time each agent spends waiting for work, and how many agents you would need to hit a target occupancy instead.
- Workload
- 33.3 erlangs
- Handling time in the interval
- 1,000.0 min
- Available time per agent
- 5.0 min
- Agents for target occupancy
- 40
Time each agent spends waiting for the next contact.
Show the working
- Handling time = 200 × 300 s ÷ 60 = 1000.0 minutes of work in the interval.
- Staffed time = 40 agents × 30 min = 1200 minutes.
- Occupancy = 1000.0 ÷ 1200 = 83.3% (the same as 33.3 erlangs ÷ 40 agents).
- Agents for 85% occupancy = 33.3 ÷ 0.85 = 39.2, rounded up to 40.
Doing this for every interval of the week? Pebble WFM computes the requirement from your forecast and builds the roster. Free month, no card needed.
How occupancy is calculated
Occupancy is handling time divided by staffed time. Contacts multiplied by handle time gives the minutes of work in the interval; agents multiplied by interval length gives the minutes of staffed time. The same number falls out of erlangs divided by agents, which is how the Erlang C calculator reports it.
Occupancy and service level pull against each other. Because contacts arrive at random, agents need slack to absorb bunching. Push occupancy towards 100 per cent and every arrival finds a queue; the relationship is not linear, and the last few points of occupancy cost a lot of service level.
The target occupancy figure works backwards: workload divided by the target gives the agents that would hold occupancy at that level. Planners use a ceiling of around 85 per cent for voice as a guard against burnout, and a lower one for small teams, where the same occupancy means longer waits.
Read the full guide: How to calculate occupancy in a contact centre
Frequently asked questions
- What is a good occupancy for a contact centre?
- For voice, 80 to 85 per cent is a common target; above 90 per cent for long stretches leads to fatigue, absence and attrition. Small queues need lower occupancy to hit the same service level, and blended or back-office work can run higher because the work waits rather than the customer.
- What is the difference between occupancy and utilisation?
- Occupancy is handling time divided by logged-in, available time. Utilisation is handling time divided by paid time, so it also absorbs shrinkage. An agent can be 85 per cent occupied and 55 per cent utilised.
- Why is my occupancy over 100%?
- There is more handling work in the interval than staffed minutes to do it. Contacts will queue and some of the work spills into the next interval, so real occupancy caps at 100 per cent and service level collapses. Either more agents are needed or the volume or handle time is misstated.
- How does occupancy relate to Erlang C?
- Erlang C picks the smallest agent count that meets a service level, and that count implies an occupancy. If the implied occupancy is above your ceiling, add agents until it is not. The staffing requirement calculator does this automatically.
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