UUID v3 Generator

Generate deterministic name-based UUID v3 identifiers from a namespace UUID and name.

Inputs
Choose a namespace UUID and name. UUID v3 hashes both values, so the same pair always returns the same UUID.

Use one of the standard namespaces or paste any valid UUID.

Standard namespaces

DNS, URL, OID, and X.500 are the standard namespace UUIDs defined for name-based UUIDs.

This can be a domain, URL, path, username, or any stable string you want to identify.

UUID v3
The result updates locally as you edit the namespace or name.

The result updates locally as you edit the namespace or name.

Version 3RFC 4122 variantDeterministic

What is UUID v3?

UUID v3 is a name-based UUID format. It takes a namespace UUID and a name, hashes them with MD5, and formats the result as a standard UUID. The important behavior is determinism: the same namespace and name always produce the same UUID.

This tool runs entirely in your browser. The namespace, name, and generated UUID stay on your device unless you copy the result elsewhere.

When to use it

  • Use UUID v3 when you need a stable identifier for a known name, such as a DNS name, URL, object path, or username.
  • Pick the namespace that matches the kind of name you are identifying. DNS and URL are the most common presets.
  • Reuse the same namespace consistently. Changing the namespace changes every generated UUID, even when the name stays the same.
  • Prefer UUID v5 or another modern identifier when you have a choice and need a name-based UUID with a stronger hash. UUID v3 exists for compatibility with systems that specifically expect MD5-based UUIDs.

Notes on safety

UUID v3 is not a random ID and is not secret. Anyone who knows the namespace and name can regenerate the same UUID. Do not use it for passwords, session tokens, API keys, or other values that must be unpredictable.