Port
Port 43 — WHOIS
Port 43 (TCP) is used by WHOIS. Domain registration lookup service.
Port 43 at a glance
| Property | Value |
|---|---|
| Port number | 43 |
| Transport | TCP |
| Service | WHOIS |
| Category | Well-known port |
What it is used for
Domain registration lookup service.
Security considerations
Low risk; informational.
See our full TCP/UDP port reference and learn how firewalls filter ports in the CyberOps course.
Frequently asked questions
What is port 43 used for?
Port 43 (TCP) is used by WHOIS. Domain registration lookup service.
Is port 43 TCP or UDP?
Port 43 uses TCP.
Is it safe to open port 43?
Low risk; informational.
Related
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