Random IP generator

Use the random IP generator for test data

This random IP generator creates address strings inside your browser. Choose IPv4 or IPv6, set a count from one to 100, and select an address pool before pressing Generate addresses. The default produces ten different IPv4 documentation addresses. Opening the page does not generate a batch, contact a generated destination, or change your connection's public address.

Start with Documentation when preparing examples, screenshots or offline test fixtures. The random IP generator uses ranges reserved for that purpose instead of borrowing an ordinary organization's address. For a private-address parser test, choose Private / local. Select Public candidates only when your data needs addresses outside this tool's special-purpose exclusions; the label does not mean that a destination is reachable.

The random IP generator supports a narrower range through Range and duplicates. Enter an optional CIDR such as 192.0.2.0/28. The filter intersects the selected pool, so a private prefix combined with Documentation produces an explanatory error. It does not silently switch modes or ignore your restriction. Leave the field empty to sample from the entire selected pool.

For a concrete exercise, keep IPv4 and Documentation, enter 192.0.2.13/28, and request ten addresses. The random IP generator normalizes that input to 192.0.2.0/28, reports sixteen eligible addresses and notes that host bits were cleared. The output contains ten distinct members of that interval. These are address literals for test data, including possible boundary values, rather than a list of assignable hosts.

Choose a random IP generator pool deliberately

The random IP generator's IPv4 documentation pool contains 192.0.2.0/24, 198.51.100.0/24 and 203.0.113.0/24. Together they contain 768 address literals. RFC 5737 reserves these blocks for examples. They are useful in published material, but they are not ordinary public destinations and should not be used as a live integration service.

For IPv6 examples, the random IP generator includes both 2001:db8::/32 and 3fff::/20. The first is defined by RFC 3849; the larger block was added by RFC 9637. Sampling is weighted by address count, so the larger block will dominate an unrestricted batch. Enter 2001:db8::/32 as the CIDR filter if you specifically need the familiar prefix.

The random IP generator's IPv4 private pool comprises the three RFC 1918 blocks: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. Shared carrier space, loopback and link-local ranges are separate categories and are not included in this choice. A generated private address may already be used on your own network; this page performs no conflict detection.

The IPv6 private option draws from fd00::/8, the locally assigned half of the unique-local space described in RFC 4193. This random IP generator creates individual test strings. It does not design a site's addressing plan, reserve a consistent ULA prefix for an organization or configure router advertisements. Use deliberate network planning before assigning addresses to real interfaces.

Understand random IP generator results

The random IP generator labels each batch with its family, selected pool and duplicate policy. The eligible-address count is exact, including for enormous IPv6 intervals. It counts the addresses that satisfy the pool and optional CIDR together. It is not a count of online devices, free addresses, registered owners or available connections. No scan occurs while calculating it.

Use One per line when pasting into a plain-text fixture. Choose JSON array when you need quoted strings in a JSON document. The random IP generator changes only the presentation when you switch copy format; it preserves the existing batch. Copy batch writes those addresses without headings, row numbers or the explanatory notes. Confirm your destination expects an array rather than a single address.

The random IP generator presents IPv4 in dotted decimal and IPv6 in normalized, lowercase compressed notation. RFC 5952 explains the IPv6 text conventions. A shorter spelling is not a smaller address, and omitted zero groups still contribute to its 128-bit value. For tests of expanded notation, use the address tools or explicitly expand your fixture rather than treating alternate spellings as different devices.

With No duplicates in this batch selected, the random IP generator samples without replacement. Requesting more unique values than the eligible space contains produces an error with the exact capacity. For example, an IPv4 /30 contributes four literals when it lies entirely inside your pool. You can request all four, but not five different members of that same interval.

If repeats are allowed, the random IP generator samples independently with replacement. A /32 IPv4 filter or /128 IPv6 filter can then produce the same single address repeatedly. Duplicate policy applies only to this operation. Separate batches may overlap, and the page does not maintain a global history or promise uniqueness across visitors, tabs or later generations.

What counts as a public candidate here?

The random IP generator's IPv4 public policy starts with the 32-bit address space and removes its recorded special-purpose blocks, multicast and reserved space. The IANA IPv4 Special-Purpose Address Registry is the primary reference. This policy excludes entire listed blocks, including special-purpose anycast ranges whose registry entries permit global reachability. The goal is ordinary candidate test data, not enumeration of every routable exception.

For IPv6, the random IP generator starts inside 2000::/3, the current assignment range identified by IANA's IPv6 address-space registry. It excludes special-purpose intersections, documentation space, transition ranges and the returned 3ffe::/16 6bone block. Addresses outside this starting range are not candidates, even if a future allocation policy might eventually make them usable.

The random IP generator uses a versioned range policy reviewed on September 28, 2026. It does not download a registry or a BGP table during generation. The IANA IPv6 Special-Purpose Address Registry and global unicast registry provide the reference boundaries. A later registry change needs a policy update; the date beside the result makes that limitation visible.

Public candidates may be unallocated, unannounced, firewalled or already assigned to someone else. The random IP generator does not obtain permission to use them. For an actual integration test, use a service or test endpoint you control and expect to answer. If your application normally sends traffic to every imported address, keep generated fixtures in an isolated test path with that behavior disabled.

How the random IP generator samples large spaces

The random IP generator obtains bytes through the browser's Web Crypto random-value API. Missing or failing cryptographic randomness produces an error. The implementation does not fall back to the clock, visitor address or Math.random. A batch is returned only after all requested values are ready, so a source failure cannot be mistaken for a complete result.

The random IP generator represents eligible intervals and their lengths with exact integers. It chooses a rank across the combined address count, then maps that rank into the corresponding interval. Larger blocks contribute more possibilities because they contain more addresses. Giving each block an equal chance would produce a different distribution, and would overrepresent smaller blocks in a mixed-size pool.

The random IP generator masks unused bits and rejects draws outside the required integer bound. It avoids the bias that direct remainder mapping can introduce for uneven bounds. Sampling without replacement uses a sparse index swap, so generating a small IPv6 batch never allocates an array covering the entire address space. Each random draw also has a finite retry budget to keep failures bounded.

The random IP generator includes the first and last eligible literals; it does not apply a universal rule that removes every IPv4 address ending in .0 or .255. Host usability depends on the actual subnet and protocol context. For network boundaries and host semantics, use the subnet calculator. To merge, split or cover complete ranges, use the CIDR calculator.

Random IP generator privacy and limits

This random IP generator has no generation API, destination lookup or probe request. Settings and generated values remain in the current page's working memory. The tool does not put them into URLs, analytics events, local storage or session storage. Ordinary page delivery and site analytics remain separate network activity. Local generation does not imply that visiting the website makes no network requests.

Changing a generation setting removes the previous result, preventing a stale batch from appearing under new options. The random IP generator's Clear button resets the controls and output. Navigating to another page also discards them, including when a destination is still loading and you immediately return. Following a section link within this article keeps the current batch available for comparison with the explanation.

Copying deliberately transfers values out of the random IP generator to your system clipboard. Clipboard history, synchronization or the application where you paste may retain them. Clearing this page does not erase those copies. If you need repeatable test data, save an approved fixture in your own project; the generator does not accept a deterministic seed or recover an earlier batch.

The random IP generator is useful for address parsing, database fixtures, sorting checks and interface layouts. Random valid inputs do not replace a deliberate edge-case suite. Add explicit cases for loopback, invalid syntax, scoped IPv6, boundaries and mixed address families according to your application's contract. Review network behavior separately, because a valid literal can still be an inappropriate connection target.

Random IP generator questions

Will the random IP generator change my IP address?

No. The random IP generator creates strings for your use as test data. It does not change a browser's network route, configure a VPN or assign a new address to your internet connection. The homepage shows the public address observed for your actual request. A generated candidate and that observed connection address describe different things.

Can the random IP generator find unused addresses?

No. The random IP generator does not query DHCP leases, neighboring devices, registries or routing tables while creating a batch. It cannot identify a safe unoccupied address on your LAN or reserve public space. For deployment, work within the address allocation and configuration process of the network you control. Treat an unanswered probe as a separate observation, not proof of availability.

Why does the random IP generator reject my CIDR?

The random IP generator requires a complete address and valid prefix length in the selected family. URLs, ports, zone identifiers and ambiguous leading-zero formats are rejected. An otherwise valid prefix can also have no intersection with the chosen pool. Check both controls: 10.0.0.0/24 belongs with the private option, while 2001:db8::/48 requires IPv6 and Documentation.

Does the random IP generator work offline?

After the page and its tool code have loaded, the random IP generator can create another batch without a remote generation service. Loading a fresh page offline is not guaranteed, and clipboard access still depends on browser support and permissions. Copy-format selection remains local. No address is contacted to make offline output look more realistic.

Can the random IP generator prove my validator is correct?

A random IP generator supplies varied examples, not a correctness proof. Keep expected results for carefully chosen fixtures and compare your parser's behavior against its documented contract. This tool's own checks cover exact interval boundaries, exclusion policy, tiny-space exhaustion, rejection sampling, duplicate control and browser lifecycle behavior. Its range policy is transparent, but it does not certify another application's validation or security decisions.