NirSoft is listing all major IP address blocks allocated for each country.
For countries in Europe and in the Middle East, the name of the company/Internet provider that own these IP blocks is also displayed. In order to show only the major IP blocks, only IP blocks with 4096 addresses or more were added to the list. For United States, only IP blocks with 65536 addresses or more were added to the list.
How can this list be used
Here are several scenarios when this list may be useful:
- When you need to identify the location of a particular IP. This could be, for example, the IP of the person that sent you an email.If you don’t know how to get the IP address of the sender you should also read:
- If you are a web developer and need to test your web application for geo-targeting. This is the case when you web application geo-targets content based on the end user’s IP address. You can do this by enabling and Modifying the X-Forwarded-For header in the HTTP Request, for which I recommend using the Modify HTTP Headers Firefox add-on.
- You can develop your own script to figure out the location of an IP address and use it, for example, to create a What Is My IP page.
[Major IP Addresses Blocks By Country]

