Finding local IP addresses using Python's stdlib

Question

How can I find local IP addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?

Answer 1

This method returns the "primary" IP on the local box (the one with a default route).

• Does NOT need routable net access or any connection at all.
• Works even if all interfaces are unplugged from the network.
• Does NOT need or even try to get anywhere else.
• Works with NAT, public, private, external, and internal IP's
• Pure Python 2 (or 3) with no external dependencies.
• Works on Linux, Windows, and OSX.

Python 3 or 2:

import socket
def get_ip():
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    try:
        # doesn't even have to be reachable
        s.connect(('10.255.255.255', 1))
        IP = s.getsockname()[0]
    except Exception:
        IP = '127.0.0.1'
    finally:
        s.close()
    return IP

This returns a single IP which is the primary (the one with a default route). If you need instead all IP's attached to all interfaces (including localhost, etc), see this answer.

If you are behind a NAT firewall like your wifi box at home, then this will not show your public NAT IP, but instead your private IP on the local network which has a default route to your local WIFI router; getting your wifi router's external IP would either require running this on THAT box, or connecting to an external service such as whatismyip.com/whatismyipaddress.com that could reflect back the IP... but that is completely different from the original question. :)