UUID Generator

Generate random UUID v4 identifiers

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About UUID Generator

A UUID (Universally Unique Identifier) is a 128-bit identifier that is practically guaranteed to be unique across space and time. This tool generates version 4 UUIDs, which are based on random numbers using the browser's cryptographically secure crypto.randomUUID() API. UUIDs are widely used as database primary keys, session IDs, and distributed system identifiers.

Q: What is UUID v4?

UUID v4 is generated using random or pseudo-random numbers. It's the most commonly used version because it requires no coordination between systems. The format is xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where 4 indicates version 4.

Q: Can two UUIDs ever collide?

Theoretically yes, but the probability is astronomically low. You would need to generate about 2.71 quintillion UUIDs to have a 50% chance of a single collision. For practical purposes, they are unique.

Q: Should I use UUID or ULID?

UUIDs are universally supported and well-understood. ULIDs are sortable by creation time, which is useful for database indexing. Choose UUID for compatibility, ULID for time-ordered requirements.