Erlang Staffing Calculator

Estimate the number of agents needed to meet your service level goals using the Erlang C staffing model — the industry-standard formula used in contact centers, help desks, customer support teams, and emergency dispatch operations worldwide.

Originally developed by Agner Krarup Erlang, a Danish mathematician and engineer, in the early 1900s while working for the Copenhagen Telephone Company, Erlang’s work focused on solving a growing problem in telephone networks: predicting congestion and determining the right number of operators and phone lines needed to efficiently handle incoming calls.

His mathematical models became the foundation of modern queueing theory — the science of waiting lines, traffic flow, and resource allocation. More than a century later, Erlang formulas are still widely used in:

• Customer service call centers
• Technical support teams
• 911 and emergency dispatch centers
• IT help desks
• Sales and reservation centers
• Healthcare scheduling systems
• Cloud and telecommunications infrastructure

The Erlang C formula helps organizations answer critical staffing questions such as:

• How many agents are needed?
• How long will customers wait?
• What service level can be achieved?
• How busy will agents be?
• What happens during peak traffic periods?

This calculator uses your call volume, average handle time, target response goals, and occupancy assumptions to estimate the staffing levels required to maintain efficient operations while balancing customer experience and operational costs.

Whether you manage a small support desk or a large enterprise contact center, the Erlang Staffing Calculator provides a practical way to model workforce requirements and improve scheduling accuracy.