UUID Generator FAQ

Q: What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. UUIDs are typically displayed as 32 hexadecimal digits separated by hyphens, like 550e8400-e29b-41d4-a716-446655440000. The standard is defined in RFC 9562. Our free UUID generator lets you generate them instantly.

Q: What is the difference between UUID and GUID?

There is no technical difference. UUID (Universally Unique Identifier) is the term used in IETF standards, while GUID (Globally Unique Identifier) is Microsoft's term for the same thing. They are 128-bit values following the same format. Use our UUID generator to create them — it works for both UUIDs and GUIDs.

Q: Which UUID version should I use?

• UUID v4: Random UUID. Best for most use cases. Simple, stateless, good as database primary keys when using UUIDv7 is not an option.
• UUID v7: Time-ordered UUID (RFC 9562, 2024). Recommended for database primary keys — sortable by creation time, works well with B-tree indexes.
• UUID v1: Based on MAC address and timestamp. Rarely used today due to privacy concerns (reveals machine MAC address and creation time).

Our UUID generator supports all three versions with batch generation.