IP Address Generator

Produce up to 100 random IPv4 or IPv6 addresses, or list the first hundred addresses inside a CIDR block, for filling out test fixtures and lab configurations.

What is the IP Address Generator?

IPv4 addresses are 32 bits written as four numbers from 0 to 255. IPv6 addresses are 128 bits written as eight groups of four hex digits, because 4.3 billion IPv4 addresses stopped being enough years ago. This tool fills a list with either kind, or walks a subnet you specify address by address. Everything is drawn with the browser's ordinary random number generator, which is exactly right for dummy data and wrong for anything that has to be unpredictable.

Key Features

• Three modes: random IPv4, random IPv6, or sequential subnet listing
• Requests of 1 to 100 addresses, with anything higher clamped to 100
• Subnet mode accepts CIDR notation and starts at 192.168.1.0/24
• Copy All puts the whole list on your clipboard, one per line
• Switching mode regenerates the list without touching the Generate button

Common Use Cases

• Filling a database seed file with plausible-looking client addresses for a demo
• Producing a block of allow-list entries to test firewall rule parsing
• Enumerating the opening hosts of a lab subnet before assigning them to machines
• Feeding a log parser sample records that contain varied source addresses

How to Use the IP Address Generator

1. Choose IPv4, IPv6 or Subnet Range from the three buttons at the top.
2. For either random mode, set Number of IPs to anything from 1 to 100.
3. For Subnet Range, type a network in CIDR form such as 10.0.0.0/24.
4. Click Generate IP Addresses to refresh the list with a new draw.
5. Use Copy All to take the whole list as newline-separated text.

Tips for Best Results

• Subnet mode ignores the Number of IPs field and always lists up to a hundred addresses.
• It also counts upward from the network address rather than picking at random.
• Random IPv4 mode draws from the entire address space, so genuinely routable addresses will appear.
• For anything you publish, use the reserved documentation ranges 192.0.2.0/24 or 2001:db8::/32 instead.

Why Use WiserWork's IP Address Generator?

Hand-writing fake IP addresses is tedious, and people end up typing 192.168.1.1 forty times, which hides the bugs that only surface with varied input. Generating a hundred takes one click and gives a spread wide enough to expose sloppy parsing. One limitation worth naming: the random modes do not skip reserved, multicast or broadcast blocks, so treat every result as test data rather than as an address that is safe to contact.

Who Uses the IP Address Generator?

Backend and network engineers use it when a fixture file needs fifty addresses that are not all identical. QA teams lean on it to check that address validation and sorting behave under pressure. It is also handy for anyone studying for a networking certification who wants a pile of addresses to practice classifying.

Frequently Asked Questions

What is the difference between IPv4 and IPv6?

IPv4 is 32 bits, roughly 4.3 billion addresses, written as four dotted decimals. IPv6 is 128 bits, written as eight colon-separated hex groups, and the space is large enough that exhaustion is not a practical worry.

Which IPv4 ranges are private?

Three blocks are set aside for private use: 10.0.0.0/8, 172.16.0.0 through 172.31.255.255, and 192.168.0.0/16. Packets addressed to them are not routed across the public internet.

Does random IPv4 mode stay inside private ranges?

No. It picks each of the four octets independently from 0 to 255, so results land on public, multicast and reserved addresses as readily as private ones. Use Subnet Range with a private CIDR when you need private addresses only.

Can these addresses belong to a real machine?

Yes, which is exactly why they are for testing and documentation only. Never point a scan, a load test or a published example at an address this tool produced.

Why does the subnet list start at the network address?

It counts sequentially from whatever you typed. For 192.168.1.0/24 the first entry is 192.168.1.0, the network identifier itself, which is not assignable to a host.

Why do I only get 100 addresses from a /16?

The listing is capped at 100 entries whatever the prefix contains. A /30 returns all four of its addresses, but anything wider than /25 gets truncated at a hundred.

Why do the IPv6 results never contain a double colon?

The generator writes all eight groups out and drops leading zeros within each group. It never applies the double-colon shorthand for a run of zero groups, so the output is valid but longer than the canonical form.

Which addresses should I use in documentation?

The blocks reserved for exactly that: 192.0.2.0/24, 198.51.100.0/24 and 203.0.113.0/24 for IPv4, and 2001:db8::/32 for IPv6. None of them will ever be assigned to anyone.

What happens if I type an invalid subnet?

There is no validation. A malformed entry falls through to zeros and you get a list starting at 0.0.0.0, and a missing prefix length is quietly treated as /24.

Is the randomness suitable for security work?

No. It uses Math.random, which is fast and evenly spread but predictable. Anything that must be unguessable needs a cryptographic random source instead.

Test data that all looks the same is how address-parsing bugs survive to production. A hundred varied addresses take one click here, and if you need them confined to a particular network, Subnet Range will walk it for you.