What is using port 80 on my Mac?

A listener on port 80 means a local web server (nginx, Apache, or a dev server) is serving plain HTTP. macOS doesn't run a web server on 80 by default. Run sudo lsof -i :80 to identify it.

Is it safe to kill a process on port 80?

If it's a local web server you started, yes. Nothing in macOS depends on a port 80 listener by default, so killing it just stops that server.

Why use port 80 instead of 8080?

Port 80 is the default for HTTP, so URLs don't need a port number. 8080 is an alternative used for development and proxies because binding 80 requires admin rights.

Port 80: What's Using It and Is It Safe to Kill?

Port 80 is the default port for HTTP, unencrypted web traffic. Modern browsers now try HTTPS on 443 first for a typed address, but plenty of traffic still reaches 80 through explicit http:// links and server redirects. A process listening on 80 on your Mac means a local web server.

What typically listens on port 80

Local web servers: nginx, Apache, and Caddy use 80 for plain HTTP.
Dev servers: Some local setups serve on 80, though 8080 and 3000 are far more common to avoid needing admin rights.
Redirect servers: A server that catches HTTP and redirects to HTTPS listens on 80.

Port 80 is in the well-known range (0-1023), so binding it requires admin privileges. macOS does not run anything on 80 out of the box.

Is it safe to kill?

Yes, if it’s a local web server you started. Stopping it frees the port and affects nothing in macOS, which doesn’t depend on a port 80 listener. Just confirm you aren’t ending a server you still need.

Is it suspicious?

On a machine where you don’t run web servers, an 80 listener is worth a look. Identify the owning process; if it’s nginx, Apache, or a dev tool you installed, it’s expected. An unfamiliar process binding 80 (which needs admin rights) is worth investigating.

How to find what’s on port 80 on macOS

sudo lsof -i :80

Use sudo because the process binding 80 typically runs as root. To stop it by PID:

sudo kill $(sudo lsof -ti :80)

For how 80 relates to the other web ports, see Common ports and what they’re used for. Portie shows port 80 with its owning process in its live list, so you can tell immediately which server is running.