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UUID Generator

Generate UUID v1, v4, v5 and v7 identifiers instantly in your browser. Choose time-based, random, namespace+name or time-ordered UUIDs, generate batches of up to 1000, and control letter case and hyphens — with cryptographically secure randomness. Private, no uploads.

Options

Random UUID using cryptographically secure browser randomness (crypto.getRandomValues — never Math.random).

Up to 1,000 UUIDs per batch.

Letter Case
Hyphens

About this generator

  • All UUIDs are generated locally in your browser. Nothing is uploaded.
  • Random UUIDs use cryptographically secure browser randomness.
  • UUIDs are identifiers, not secrets — never use them as passwords or keys.

UUIDs are generated locally in your browser and are never uploaded.

UUID v4 and v7 use cryptographically secure browser randomness. UUIDs are identifiers, not secrets — they are not passwords, encryption keys, or authentication tokens. A very large random identifier space makes collisions astronomically unlikely, but no finite random system can guarantee absolute impossibility.

How it works

  1. 1Choose a UUID version. Pick UUID v1 (time-based), v4 (random), v5 (namespace + name) or v7 (time-ordered). A short description explains each version.
  2. 2Set quantity and formatting. Choose how many UUIDs to generate (1–1000) and the letter case and hyphen style. For v5, enter a namespace (DNS, URL, OID, X.500 or a custom UUID) and a name.
  3. 3Generate your UUIDs. Click Generate UUIDs (or Generate Again for new random values). v4 and v7 use cryptographically secure browser randomness — never Math.random.
  4. 4Copy or download. Copy any single UUID, copy all of them one per line, or download a generated-uuids.txt file — all locally in your browser.

Best practices

  • Use v4 for general-purpose identifiers: it is random, universally compatible and needs no inputs.
  • Use v5 when you need the same name to always produce the same UUID — deterministic IDs for stable references.
  • Use v7 for time-ordered IDs when values sort naturally by creation time, such as database primary keys.
  • Treat UUIDs as identifiers, not secrets — never use them as passwords, API keys or authentication tokens.
  • For v1, remember this tool never reads your device MAC address: it uses a generated random node identifier.
  • Batches are checked for uniqueness, and v5 quantity is fixed at 1 because the same namespace + name is always identical by design.
  • Everything runs locally in your browser with cryptographically secure randomness — nothing is uploaded.

Frequently Asked Questions

What does UUID Generator do?
It generates RFC-compliant UUID identifiers locally in your browser. You can create time-based v1, random v4, deterministic v5 (namespace + name), and time-ordered v7 UUIDs — one at a time or in batches of up to 1000 — with letter-case and hyphen formatting controls.
What is UUID v4?
UUID v4 is a random identifier whose 122 random bits come from a cryptographically secure source (crypto.getRandomValues in your browser — never Math.random). It is the most common version for database keys and general identifiers.
What is UUID v1?
UUID v1 is a time-based identifier built from a timestamp, a clock sequence and a node identifier. By default, some implementations derive the node from the device MAC address — this tool does not. It uses a generated random node identifier and never reads your device MAC address.
Does this UUID v1 generator use my MAC address?
No. The tool uses the uuid library's random node identifier, which is generated locally and is not a real unicast MAC address. No browser API for hardware addresses is ever called, and nothing is uploaded.
What is UUID v5?
UUID v5 is a namespace-based identifier computed with SHA-1 from a namespace UUID and a name (such as a DNS domain or URL). It is fully deterministic: the same namespace and name always produce the same UUID, which makes it useful for stable, reproducible identifiers.
Why does UUID v5 produce the same result?
That is by design. v5 is a deterministic hash of namespace + name, so repeating the same input always yields the same UUID. This is not a bug — it is exactly what makes v5 useful for stable IDs. For this reason the tool fixes quantity at 1 for v5.
What is UUID v7?
UUID v7 is a time-ordered identifier defined in RFC 9562. It embeds a 48-bit Unix timestamp in the most significant bits and fills the rest with randomness, so values generated close together sort in timestamp order — useful for database indexes.
What is a GUID?
GUID (Globally Unique Identifier) is Microsoft's name for the same 128-bit identifier family as UUID. The UUID Generator's v4 output is equivalent to a standard random GUID and can be used anywhere a GUID is expected.
Can I generate UUIDs in bulk?
Yes — up to 1000 UUIDs per batch for v1, v4 and v7. Batches are checked for uniqueness, and the results can be copied one per line or downloaded as a TXT file. Quantity is fixed at 1 for deterministic v5.
Can UUIDs collide?
UUID v4 provides a very large random identifier space (122 random bits), making collisions astronomically unlikely — but no finite random system can guarantee absolute impossibility. Batch generation here also checks for duplicates and regenerates rather than silently emitting them.
Are UUIDs secret?
No. UUIDs are identifiers, not secrets. They are not passwords, encryption keys or authentication tokens, and a UUID alone must never be used to protect or authorize access.
Is anything uploaded?
No. UUIDs are generated entirely in your browser using local cryptographic randomness. No server call is made, nothing is uploaded, and no account is required.

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Supported UUID versions

Generate RFC 4122 / RFC 9562 compliant UUIDs directly in your browser: v1 (time-based, with a random node identifier — never your MAC address), v4 (random, cryptographically secure), v5 (namespace + name, deterministic, with DNS, URL, OID, X.500 or custom namespaces) and v7 (time-ordered). Batches of up to 1000 are supported for v1, v4 and v7, with lowercase/uppercase and hyphen formatting. Everything runs locally — no uploads.

Privacy & data removal

Your UUIDs are generated entirely in your browser using local cryptographic randomness and are never uploaded to any server. No account is required to use the UUID Generator, and we never store or share your namespaces, names or generated identifiers. This tool also never reads your device MAC address when generating v1 UUIDs.