ErlangC calculator

The calculator below provides an estimate of the number of inbound call centre advisors required to satisfy a customer service goal. It uses the ErlangC equation applied to a 30 minute period.

The calculator returns the number of inbound advisors that should be made available, and does not make an allowance for absences such as meetings, sickness or absence. Therefore, you should schedule more than this number in order to ensure that the required number are logged on at the right time.

calls offered within half hour
average call handling time (incl. wrap) in seconds
target answer time in seconds (eg 20)
% of calls answered within target time (eg 80)

Other algorithms and methods are required to calculate resource requirements in outbound, blended, multichannel and multiskilled environments.

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