GlossaryNetworkingBeginner

IPv4

IPv4 is the fourth and most widely used version of the Internet Protocol, giving every connected device a numeric address like 192.168.1.1. It supports about 4.3 billion unique addresses.

Last updated June 8, 2026

Definition

IPv4 (Internet Protocol version 4) is the addressing system that has powered most of the internet since the early 1980s. It assigns each device a 32-bit numeric address, written as four numbers from 0 to 255 separated by dots, such as 203.0.113.42.

How it works

Because IPv4 uses 32 bits, it can represent roughly 4.3 billion unique addresses. Every packet sent over the internet carries a source and destination IPv4 address so routers know where to deliver it. As the world ran out of free addresses, techniques like NAT and CGNAT emerged to let many devices share a single public IPv4 address.

Why it matters for proxies and scraping

IPv4 addresses are scarce and valuable, which is why they dominate the proxy market. The vast majority of websites and anti-bot systems are tuned for IPv4, so residential, datacenter, and mobile proxies are almost always sold as IPv4 addresses. Their scarcity also means clean, unflagged IPv4 ranges command premium prices and that abused addresses are hard to replace.

  • Identify and route devices on the internet
  • Power virtually all commercial proxy pools
  • Share one public IP via NAT and CGNAT

Examples

1

192.168.1.1 (a home router)

2

8.8.8.8 (Google public DNS)

3

203.0.113.42 (a public website server)

Common Use Cases

Addressing devices across the internet
Buying IPv4 residential or datacenter proxies
Sharing one public IP through NAT
Geo-targeting based on IP location

Frequently Asked Questions

About 4.3 billion, because the format uses 32 bits. That pool has effectively run out, which drove the creation of NAT, CGNAT, and the newer IPv6 standard.
Websites and anti-bot systems are built around IPv4, and its scarcity makes clean addresses valuable. As a result, nearly all commercial proxy services sell IPv4 IPs for the best compatibility.

Keep Learning

All terms

Residential Proxy

A residential proxy routes your traffic through a real device with an IP assigned by an Internet Service Provider, so requests appear to come from a genuine home user rather than a server.

Read definition

Datacenter Proxy

A datacenter proxy is an IP address hosted on servers in a data center rather than assigned by an ISP — offering high speed and low cost, but easier for websites to detect.

Read definition

CGNAT (Carrier-Grade NAT)

CGNAT is a technique carriers use to share one public IP among many customers — which is exactly why mobile proxy IPs are so trusted and hard to block.

Read definition

Geo-Targeting

Geo-targeting is selecting proxy IPs from a specific country, region or city so your requests appear to originate from that exact location.

Read definition
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