๐ UUID v5 Generator (Namespace-based)
The same namespace and name combination always produces the same UUID (RFC 4122 UUID v5, SHA-1 based).
Enter a valid namespace UUID and name
Enter a namespace UUID and a name string to generate an RFC 4122 UUID v5. Unlike random UUID v4s, a UUID v5 is deterministic (SHA-1 hash-based) โ the same namespace and name combination always produces the same UUID.
How to use
- Select a namespace (the standard DNS, URL, OID, or X.500 namespace, or a custom UUID).
- Enter a name (any string).
- The generated UUID v5 is shown automatically.
FAQ
What's the difference between UUID v4 and v5?
UUID v4 is fully random, generated from cryptographic randomness. UUID v5 is deterministic โ it's generated by SHA-1 hashing a "namespace UUID" and a "name" together, so the same input always produces the same result.
What are the standard namespace UUIDs?
RFC 4122 defines four standard namespace UUIDs: DNS, URL, OID, and X.500. For example, generating a UUID v5 from the DNS namespace and "python.org" always produces the same value (886313e1-3b8a-5372-9b90-0c9aee199e5d).
What's this useful for?
It's handy when you want a reproducible ID derived from a known string (like a URL or domain name), or when you need to deterministically assign unique IDs rather than generating random ones.