How do I change my IP address?

The IP address of your actual device (phone, tablet, desktop PC or laptop) is most likely determined by the network you are on. It will usually be allocated by a DHCP server – in a business it will likely be a dedicated server managed by the network administrator, at home it is likely to be your router that connects you to the Internet. So in either case it is changed at the discretion of the DHCP server database or IP address pool.

In most cases this address is an internal, often private address. (If so it will be in the range defined by RFC1918, and look like 10.x.x.x, 192.168.x.x or 172.16-31.xx). The address that the Internet sees you as will be a public address. This may be the external address on your router, or it could be only allocated deeper in your ISP. The mapping between your address on your machine and the Internet public address is called NAT, Network Address Translation. If you talk to your network administrator or your ISP you may be able to arrange for a fixed public address allocation for you. You can also arrange with your local Regional Internet Registry (RIR) to allocate you address space, which is then used in your connection to your ISP.

You can ask Google to tell you what it thinks your public IP address is, by asking “What is my IP address”. This can be useful in helping understand how your own machine’s IP address differs (or not) from your public address.

So in summary, your address is mostly determined by network components such as the DHCP server, and the router performing NAT, and allocation is done by the administrator of those devices.