UUID Generator
Generate one or many UUIDs
Ready to copyv4
Spacefor newVersion
Format
Uppercase
No hyphens
{Braces}
Quantity
UUIDs
Session log
Generate a batch —
it'll appear here
0 in session
About UUID Generator
A UUID (Universally Unique Identifier) is a 128-bit label used to uniquely identify information in computer systems. UUIDs are generated without a central registry, so any system can create one independently without coordination. They are widely used as primary keys in databases, resource identifiers in APIs, and correlation IDs in distributed systems and logs.
Use cases
- →Generate primary keys for database records without a sequence
- →Create unique resource identifiers for REST or GraphQL APIs
- →Produce correlation IDs for distributed tracing and logging
- →Generate test fixtures with guaranteed unique identifiers
- →Extract UUIDs from logs or API payloads with the paste mode
FAQ
- Which version should I use?
- v4 is the right choice for most cases — it is fully random and universally supported. Use v1 if you need a time-sortable ID and do not mind exposing the creation timestamp. Use v7 for database primary keys where monotonically increasing IDs improve index performance.
- v4 — Random
- Best for most uses. Fully random with no timestamp component. Collision probability is negligible for any practical volume of IDs.
- v1 — Time-based
- Encodes the current timestamp in the first segment, making IDs sortable by creation time. Be aware that this exposes the timestamp and the MAC address of the generating machine.
- v7 — Time-ordered
- Like v1 but database-friendly. Uses a Unix millisecond timestamp in the most-significant bits, making UUIDs monotonically increasing and ideal for indexed columns in PostgreSQL, MySQL, and similar databases.
- Are these cryptographically secure?
- The browser-side generator uses Math.random(), which is sufficient for most uses but not cryptographically secure. For security-critical IDs (session tokens, API keys), use crypto.randomUUID() or a server-side library.