Port

Port 37 — Time

Port 37 (TCP) is used by Time. Legacy time protocol.

Port 37 at a glance

PropertyValue
Port number37
TransportTCP
ServiceTime
CategoryWell-known port

What it is used for

Legacy time protocol.

Security considerations

Obsolete; use NTP (123) instead.

See our full TCP/UDP port reference and learn how firewalls filter ports in the CyberOps course.

Frequently asked questions

What is port 37 used for?

Port 37 (TCP) is used by Time. Legacy time protocol.

Is port 37 TCP or UDP?

Port 37 uses TCP.

Is it safe to open port 37?

Obsolete; use NTP (123) instead.

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