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UUID Generator

The UUID Generator is a free online tool that creates RFC 4122 version 4 UUIDs individually or in bulk. Values come from crypto.randomUUID(), backed by your operating system's cryptographically secure random source, and are generated locally without any server involvement.

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What is a UUID v4?

A UUID version 4 is a 128-bit identifier whose payload is generated randomly rather than derived from a database sequence, timestamp, or device address. This generator creates one or many values in the standard 8-4-4-4-12 hexadecimal form for records, test fixtures, request IDs, and distributed systems.

Each value comes from crypto.randomUUID and contains 122 random bits after the required version and variant bits are set. Generation happens on the device using the operating system's cryptographically secure random source. UUIDs make collisions extraordinarily unlikely, but they do not prove authenticity or conceal information attached to an ID.