Online UUID Version 5 Generator

Understanding UUID Version 5 Generation

UUID Version 5 identifiers are generated by our UUID generator in a deterministic way, similar to Version 3. However, when you generate a UUID of this version, it uses the SHA-1 hashing algorithm instead of MD5. This generally results in a stronger hash, offering a lower probability of collision for the generated UUID.

Namespace UUID

A predefined or custom UUID that acts as a scope for the name when you generate a UUID. RFC 4122 defines the same standard namespace UUIDs as for Version 3 (e.g., for DNS, URL, OID, X.500) that our UUID generator can utilize.

Name

An input string that, when combined with the namespace, is used by the UUID generator to create a unique identifier.

SHA-1 Hashing

To generate the UUID, the namespace UUID and the name are concatenated. The UUID generator then computes the SHA-1 hash of this combined string.

Format Adaptation

Specific bits in the resulting SHA-1 hash are then altered by the UUID generator to conform to the UUID Version 5 format. This includes setting the version bits to '0101' (hexadecimal '5'), ensuring the generated UUID is a valid Version 5 UUID.

The format for a UUID Version 5 generated by our tool is xxxxxxxx-xxxx-5xxx-xxxx-xxxxxxxxxxxx. The '5' in the third group of hexadecimal digits clearly indicates that you've generated a Version 5 UUID.

Use Cases

Similar to Version 3, generating a UUID Version 5 is useful when you need to create a consistent UUID for a given name within a specific context (namespace). The use of SHA-1 by the UUID generator provides a stronger guarantee of uniqueness for the generated UUID compared to the MD5 algorithm used in Version 3.