UUID v5 Generator
Generate deterministic UUIDs based on a name or URL using version 5 (name-based).
Enter any text (domain name, URL, or identifier) to generate a consistent UUID. The same input will always produce the same UUID.
UUID v5 generates deterministic UUIDs from a name or URL using SHA-1 hashing. The same input always produces the same UUID.
Key characteristic: Unlike v4 (random), v5 UUIDs are reproducible. If you generate a UUID from "example.com" today and again tomorrow, you'll get the same UUID.
Use cases: Consistent identifiers for domain names, URLs, email addresses, or any data that needs reproducible UUIDs.
What is UUID v5 and how does it differ from v4?
UUID v5 generates deterministic UUIDs from a namespace and name using SHA-1 hashing. Unlike v4 (random), v5 always produces the same UUID for the same input. This is useful when you need consistent identifiers—the same domain name will always generate the same UUID.
When should I use UUID v5 instead of v4?
Use v5 when you need reproducible UUIDs from known data—like generating consistent IDs for URLs, email addresses, or domain names. Use v4 when you need random, unpredictable identifiers. V5 is ideal for data deduplication or distributed systems needing consistent references.
What is a UUID namespace?
A namespace is a predefined UUID that scopes your generated UUIDs. Standard namespaces include DNS (for domain names), URL (for URLs), OID (for object identifiers), and X500. Using different namespaces ensures the same name produces different UUIDs in different contexts.
Is UUID v5 secure for sensitive data?
UUID v5 uses SHA-1 hashing, which is not cryptographically reversible, but the input can potentially be guessed through brute force if the namespace and possible names are known. Don't use v5 for sensitive data like passwords or secrets—it's designed for identifier consistency, not security.