Generate UUID v4 and v1 identifiers with bulk generation, case options, and one-click copy
Generated using cryptographically secure random values.
Display UUIDs in uppercase letters
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A UUID (Universally Unique Identifier) is a 128-bit identifier that is unique across space and time. UUIDs are standardized by RFC 4122 and are commonly used in software development to identify resources without a central authority.
Version 4 uses cryptographically secure random numbers, making collisions extremely unlikely. Version 1 incorporates the current timestamp, providing time-ordering but potentially revealing creation time.
UUIDs follow the format xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx where M indicates the version and N indicates the variant.