What is heartbeat mechanism in WebSockets?

Updated May 6, 2026

Short answer

Heartbeat is a periodic ping-pong mechanism to check if connection is alive.

Deep explanation

Servers and clients send ping/pong messages at intervals to detect broken or idle connections. If no response is received, connection is closed.

Real-world example

Live trading systems detecting inactive clients.

Common mistakes

  • Not implementing heartbeat leading to zombie connections.

Follow-up questions

  • What is pong response?
  • Why is heartbeat needed?

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