IP Range of the USA: A Comprehensive Guide
The United States has one of the largest allocations of IP (Internet Protocol) addresses in the world. These addresses are used by internet service providers (ISPs), businesses, government agencies, and cloud providers to facilitate communication across the internet. The allocation of IP ranges in the U.S. is managed by ARIN (American Registry for Internet Numbers), which oversees IP distribution in North America.
In this article, we will explore the IP address ranges assigned to the U.S., how they are managed, and how to identify U.S.-based IP addresses.
Understanding IP Ranges
An IP range is a block of IP addresses assigned to a particular entity or geographic region. These ranges help in identifying the source and destination of internet traffic. IP addresses can be classified into two versions:
1. IPv4 (Internet Protocol version 4) – Uses a 32-bit address system, with a total of about 4.3 billion addresses.
2. IPv6 (Internet Protocol version 6) – Uses a 128-bit address system, providing a virtually unlimited number of IP addresses.
Due to the depletion of IPv4 addresses, IPv6 adoption is increasing worldwide, including in the U.S.
Who Manages IP Ranges in the U.S.?
The distribution of IP addresses is managed globally by IANA (Internet Assigned Numbers Authority), which delegates large blocks of addresses to Regional Internet Registries (RIRs). In North America, including the U.S., ARIN is responsible for allocating and maintaining IP address resources.
Major IP Ranges Assigned to the U.S.
The United States has several large IPv4 and IPv6 address blocks assigned to various entities. Below are some of the most well-known allocations.
IPv4 Ranges for the U.S.
IPv4 addresses are written in the format X.X.X.X, where each “X†is a number between 0 and 255. Here are some of the major IPv4 ranges assigned to the U.S.:
IP Range
Organization / Usage
3.0.0.0 – 3.255.255.255
Amazon Web Services (AWS)
4.0.0.0 – 4.255.255.255
Level 3 Communications (CenturyLink)
6.0.0.0 – 6.255.255.255
U.S. Department of Defense
7.0.0.0 – 7.255.255.255
U.S. Department of Defense
8.0.0.0 – 8.255.255.255
Level 3 Communications
9.0.0.0 – 9.255.255.255
IBM (Internal use)
11.0.0.0 – 11.255.255.255
U.S. Department of Defense
13.0.0.0 – 13.255.255.255
Microsoft Corporation
23.0.0.0 – 23.255.255.255
Various ISPs and Cloud Providers
34.0.0.0 – 35.255.255.255
Google Cloud
44.0.0.0 – 44.255.255.255
Amateur Radio Digital Communications
52.0.0.0 – 52.255.255.255
Amazon Web Services (AWS)
These are only a few examples. The full list of U.S. IP allocations is extensive, covering a large portion of the IPv4 address space.
IPv6 Ranges for the U.S.
As IPv4 addresses become scarce, IPv6 adoption has grown. IPv6 addresses use a 128-bit format and look like this:
2600:1400::/22
Some major IPv6 ranges assigned to the U.S. include:
IPv6 Range
Organization / Usage
2001:1900::/23
ARIN’s block for North America
2600::/12
ISPs such as AT&T, Verizon, and Comcast
2620::/23
Assigned to large U.S. corporations
These IPv6 ranges are used by ISPs, businesses, and cloud services to ensure continued internet growth.
Why Does the U.S. Have So Many IP Addresses?
The U.S. was an early adopter of the internet, and many of the initial IPv4 allocations were given to American universities, corporations, and government agencies. As a result, the U.S. controls a significant portion of global IP addresses.
However, with IPv4 address exhaustion, companies and ISPs are transitioning to IPv6, which offers a much larger address space.
How to Check If an IP Address Belongs to the U.S.?
If you want to determine whether an IP address belongs to the U.S., you can use online lookup tools such as:
• IPinfo.io – Provides detailed information about IP addresses.
• ARIN Whois – The official registry for North American IP allocations.
• BGPView.io – Allows you to check routing information for specific IP blocks.
Alternatively, you can use the “whois†command in a Linux or macOS terminal:
whois 8.8.8.8
This will return ownership details of the IP address (in this case, Google).
Conclusion
The United States has one of the largest allocations of IP addresses, covering millions of IPv4 and IPv6 addresses. Managed by ARIN, these addresses are distributed across ISPs, tech companies, cloud providers, and government agencies.
With the depletion of IPv4, the transition to IPv6 is becoming increasingly necessary to support the growing demand for internet connectivity. If you need to check whether an IP belongs to the U.S., tools like IPinfo.io and whois can help verify its origin.
As the internet continues to evolve, understanding IP ranges and how they are allocated will remain crucial for network administrators, cybersecurity professionals, and researchers.