What Is NAT? Network Address Translation Explained

Quick answer: NAT lets multiple devices use one public IPv4 address by translating private network addresses and ports as traffic crosses a router.

Why NAT exists

Private addresses such as 192.168.x.x are not directly routable across the public internet. A home router translates those connections to the network’s public address. This conserves IPv4 space and also keeps internal addressing separate from the public side of the connection.

NAT and ports

NAT tracks source ports so replies can return to the correct device. This is why several phones, laptops and smart TVs can browse at the same time while sharing one public IP.

For the public address seen by websites, use the IP Lookup tool.