Port 27015: Source engine
Port 27015 is the default game and server-browser query port for games built on Valve's Source engine, including Counter-Strike and Team Fortress 2. Dedicated servers use it for both gameplay traffic and for responding to server-list queries.
| Port number | 27015 |
|---|---|
| Service | Valve Source engine game/query port |
| Protocol | TCP/UDP |
| Category | Gaming |
| Default encryption | No |
Frequently asked questions
What is port 27015 used for?
Port 27015 is the default game and server-browser query port for games built on Valve's Source engine, including Counter-Strike and Team Fortress 2. Dedicated servers use it for both gameplay traffic and for responding to server-list queries.
Is port 27015 TCP or UDP?
Port 27015 (Source engine) uses TCP/UDP.
Is port 27015 secure?
Port 27015 is not encrypted by default. Where possible, use an encrypted alternative or tunnel it over TLS or a VPN.
Should I open port 27015 on my firewall?
Only if you specifically need Source engine. Expose it to the smallest set of trusted sources, and never open database or Windows-service ports to the whole internet.