GUID / UUID Generator

A GUID (Globally Unique Identifier) — also called a UUID (Universally Unique Identifier) — is a 128-bit value used to identify information without relying on a central authority to avoid collisions. They're commonly used as database primary keys, request IDs, and session identifiers.

v4 is randomly generated and the most common choice for general-purpose unique IDs. v1 is generated from the current timestamp and a node identifier, making it sortable by creation time but less private. v5 is deterministic — it hashes a namespace and a name (such as a URL or domain), so the same input always produces the same UUID.