Generate cryptographically secure Version 4 UUIDs (RFC 4122) in bulk with custom casing, hyphens, and one-click copy.
A Version 4 UUID consists of 128 bits. In hex representation, it forms a 36-character string organized as 8-4-4-4-12:
Bits 12–15 of the third segment are fixed to 4 (denoting Version 4). The highest 2 bits of the fourth segment are set to 10 (denoting variant 1, RFC 4122). This leaves 122 bits of pure random entropy, providing 2122 (or 5.3 × 1036) unique combinations. The collision probability across billions of generated records is effectively zero.
9b1deb4d-3b7d-4bad-9bdd-2b0d7b3dcb6d
Notice the digit 4 in the third segment confirming Version 4 random generation.
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