VoIP glossary · Average Call Duration
What is ACD?
ACD (Average Call Duration) is the total billed talk time on a route divided by the number of answered calls, usually expressed in minutes.
ACD explained
ACD tells you how long real conversations last once a call connects. Alongside ASR it is one of the two numbers carriers and buyers watch most closely, because a sudden drop usually means something is wrong: calls being answered by machines, audio failing so people hang up, or false answer supervision where the far end signals "answered" before anyone picks up.
What counts as a healthy ACD depends entirely on the traffic. A call centre doing outbound sales might see two minutes, while retail calls to family abroad can average eight or more. Compare a route against its own history and against similar traffic, not against a universal target.
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