Operations answers · CMK Sons Labs
Two steps. The first is arithmetic. The second is the one people skip.
Work out your erlangs, which is simply how much continuous work arrives:
On the sample in the calculator: 500 contacts in a 30 minute interval at 300 seconds handle time is 83.33 erlangs. That is 83.33 agents' worth of continuous talking.
83.33 agents is not the answer. If you staff exactly the workload, the queue grows without limit and nobody is ever answered on time. You need more, and how many more depends entirely on how fast you have promised to answer.
Erlang C does that conversion. For the same 500 contacts at an 80/20 target, the answer is 91 agents. Those extra 8 people are not slack. They are what the service level costs.
Paste your interval volumes and handle time. It returns the agents each interval needs, which constraint binds, and the roster to cover it. Free.
Free, no signup, nothing you type is uploaded. Written by Chris Maras, who spent 21 years in operations before building these. · All ten tools