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Random IP Address Generator

Random
Restrict generated addresses to a subnet, e.g. 10.0.0.0/8 or 2001:db8::/32.
A non-negative integer for repeatable, non-secure output. Leave blank for cryptographically secure randomness.

About This Tool

Random IP Address Generator – IPv4 and IPv6 Test Data

An IP address uniquely identifies a device on a network. IPv4 addresses are written as four decimal octets separated by dots, such as 192.168.1.42, giving roughly 4.3 billion possible values. IPv6 addresses use eight groups of hexadecimal digits separated by colons, such as 2001:0db8:85a3::8a2e:0370:7334, and were introduced because the IPv4 address space is nearly exhausted. This tool generates syntactically valid addresses of either type entirely inside your browser — nothing you configure or generate is ever sent to a server.

Public, private, and special-purpose ranges

Not every address is meant to be routed across the public internet. Private ranges are reserved for internal networks: for IPv4 that's 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 under RFC 1918, while IPv6 uses fc00::/7 Unique Local Addresses. Loopback addresses (127.0.0.0/8 for IPv4, ::1 for IPv6) always refer back to the local machine. Link-local addresses (169.254.0.0/16, fe80::/10) are auto-assigned when no DHCP server responds, and multicast addresses (224.0.0.0/4, ff00::/8) target groups of listeners rather than a single host. Selecting an Address Type filter restricts generation to one of these categories, or to Public addresses that fall outside all of them.

Constraining results with CIDR notation

CIDR notation (Classless Inter-Domain Routing) combines a network address with a prefix length, like 192.168.100.0/24, to describe a block of addresses. The prefix length tells you how many leading bits are fixed as the network portion — the remaining bits vary across hosts in that subnet. Enter a CIDR range to constrain every generated address to that block; the tool computes the network and broadcast addresses and picks random values from the usable host range in between (excluding the network and broadcast addresses themselves for IPv4 prefixes of /30 or shorter). CIDR ranges apply to a single IP version, so set IP Version to IPv4 or IPv6 before entering one.

Batch controls: duplicates, sorting, and export

By default, batches of more than one address never contain duplicates — the generator keeps drawing until every value is unique, or until the constrained address space runs out (a common outcome if you request 100 addresses from a tiny /30 CIDR block). Turn on Allow Duplicates if repeats are acceptable. Sort Output Numerically orders results by their underlying numeric value instead of generation order, and Include CIDR Suffix appends a subnet mask like /24 to each address — either from the CIDR range you supplied, or a fixed length you choose. Results can be copied individually, copied as a batch, or exported as a plain text list, CSV, or JSON array.

About the reproducible seed
Leaving the seed blank uses the Web Crypto API for cryptographically secure randomness. Entering a seed switches to a deterministic pseudo-random generator so the same seed and settings always reproduce the same batch — handy for repeatable test fixtures, but not suitable for anything security-sensitive.

Common use cases

Developers use randomly generated addresses to seed test databases, populate UI mockups, and write documentation examples without exposing real infrastructure. QA engineers use them to exercise firewall rules, access-control lists, and input validation across every address class. Students studying subnetting can generate addresses within a specific CIDR block to practice identifying network and broadcast addresses, and network administrators can quickly produce sample data for scripts and configuration templates — all without the risk of accidentally using a real, in-use IP address.

Frequently Asked Questions

Is the Random IP Address Generator free?

Yes, Random IP Address Generator is totally free :)

Can I use the Random IP Address Generator offline?

Yes, you can install the webapp as PWA.

Is it safe to use Random IP Address Generator?

Yes, any data related to Random IP Address Generator only stored in your browser (if storage required). You can simply clear browser cache to clear all the stored data. We do not store any data on server.

How does the Random IP Address Generator work?

You choose an IP version (IPv4, IPv6, or both), an address type (Any, Public, Private, Loopback, Link-Local, or Multicast), and a quantity. The tool then draws random addresses that satisfy those constraints entirely in your browser using the Web Crypto API — nothing is sent to a server.

Can I generate addresses from a specific subnet?

Yes. Enter a CIDR range such as 10.0.0.0/8 or 2001:db8::/32 and every generated address will fall within that block's usable host range. CIDR ranges apply to a single IP version at a time, so switch Both to IPv4 or IPv6 first.

Are the generated addresses guaranteed to be unique?

By default, yes — duplicates are automatically skipped within a batch. You can turn on Allow Duplicates if you specifically need repeats, or if your requested quantity exceeds the number of unique addresses available in a small range.

What does the reproducible seed do?

Leaving the seed blank uses a cryptographically secure random source. Entering a non-negative integer switches to a deterministic pseudo-random generator, so the same seed and settings always reproduce the same batch — useful for repeatable test fixtures, but not suitable for anything security-sensitive.

Are these real, routable IP addresses?

They are syntactically valid and pass standard IP validation, but they are randomly generated, not looked up from any registry. Public/Any results may occasionally coincide with a real address purely by chance, so avoid using generated addresses for anything beyond testing, documentation, or mock data.

Why did I get fewer addresses than I requested?

This happens when duplicates are disallowed and the constrained space (a small CIDR block, or a narrow type like IPv6 Loopback, which has only one valid address) simply doesn't contain enough unique values to satisfy the request. A summary below the results shows how many were actually generated.