UUID v4
Random UUID generation
Generate universally unique identifiers (UUIDs/GUIDs) in multiple versions. Perfect for databases, APIs, and distributed systems.
Random UUID generation
Time-based UUID
Generate up to 1000 UUIDs
UUID format validation
Randomly generated - best for general-purpose use
| Version | Name / Type | Based On | Common Use | Status |
|---|---|---|---|---|
| v1 | Time-based | Timestamp + MAC address | Distributed systems | ✓ Supported |
| v2 | DCE Security | v1 + POSIX UID/GID | Rarely used | — Legacy |
| v3 | Name-based (MD5) | Namespace + Name | Deterministic IDs | ✓ Supported |
| v4 | Random ⭐ | Random numbers | General-purpose (most common) | ✓ Supported |
| v5 | Name-based (SHA-1) | Namespace + Name | Deterministic & secure | ✓ Supported |
| v6 | Reordered v1 | Timestamp (sortable) | Databases (new) | ✓ Supported |
| v7 | Unix Epoch Time 🆕 | Timestamp + randomness | Modern DBs (recommended) | ✓ Supported |
| v8 | Custom | User-defined | Experimental | — Experimental |
A UUID (Universally Unique Identifier), also known as GUID (Globally Unique Identifier), is a 128-bit number used to identify information in computer systems. UUIDs are standardized by RFC 4122 and the newer RFC 9562.
The probability of generating duplicate UUIDs is so low that it can be ignored for practical purposes. This makes UUIDs ideal for distributed systems where unique identifiers are needed without coordination.