Erlang Calculator - for Call Centre Staffing (2020 Update)
What is an Erlang Calculator?
An Erlang calculator is a call centre focussed mathematical calculator that can be used for multiple forecasts for call centre operations. While there are multiple types of Erlang calculators, the most commonly used calculator is the Erlang C Calculator, which is used to calculate the number of call centre agents or staff you need to meet the service levels for a given number of calls. The calculator is based on the Erlang C formula (a derivative of the Poisson distribution) that was designed by the Danish Mathematician A.K. The other types of Erlang Calculators include Erlang B, Extended Erlang B, Bandwidth Erlang and more. We will discuss those in the following sections of this post.
Service Time (sec)
Calls per Hour
Importance of Calculator
As a call centre team manager, or a call centre head, an Erlang calculator should be your best friend. It can be the most handy tool to help you forecast and report multiple metrics, numbers to your executive team and also plan your call center operations better. As we all know, call centre is one of the busiest and most important customer facing functions in a company, it is important to plan it well from all aspects – staffing, quality, forecasting and more. Research says that one of the most high priority goals of executives is to reduce the inbound calls to a call centre and improve call centre operations, quality. To achieve such goals, an Erlang calculator is a must.
So what can an Erlang calculator do for call centre executives?
An Erlang calculator can help with multiple things like estimate how many lines you need in your trunk groups if you know that traffic that will be offered to your system, or estimate how many agents or operators you need to answer calls at your inbound call center or help desk. But the Erlang calculator is not just limited to these. Let’s take a look at the different types of calculators in the next section. Types of Erlang Calculators While the most commonly used Erlang calculators are Erlang C (staffing calculator) and Erlang B (number of lines needed), in this section we are going to talk about types of Erlang Calculators and what each of them can do for your call centre. They are based on the industry-standard Erlang traffic models, established in the first half of the last century to analyse telecommunications systems.
Erlang B calculator
Estimate how many lines you need in your trunk groups if you know that traffic that will be offered to your system.
Erlang C calculator
Estimate how many agents or operators you need to answer calls at your inbound call center or help desk.
Call minutes calculator
Estimate how many lines your telecom system needs if know the daily minutes it must switch.
VoIP bandwidth calculator
Calculate the bandwidth you require to transport a fixed number of voice paths through your IP network.
Erlang bandwidth calculator
Estimate how much bandwidth you need to carry your busy hour traffic in Erlangs.
Extended Erlang B
Similar to Erlang B but takes into account that a percentage of calls are immediately repeated if they are blocked.
Estimate how many lines your trunk groups need when you have a finite number of traffic source.