Generate universally unique identifiers
A UUID is a 128-bit identifier written as 36 characters (32 hex digits plus 4 hyphens) that can be generated independently on any machine with a negligible chance of collision.
SnoopTool generates version 4 UUIDs from the browser's cryptographic random source and can produce them in bulk. A v4 UUID has 122 random bits; you would need to generate about 2.7 × 10¹⁸ of them before a 50% chance of any collision.
| Format | 8-4-4-4-12 hex characters, e.g. 3f2504e0-4f89-41d3-9a0c-0305e82c3301 |
|---|---|
| Version 4 | Randomly generated; 122 random bits |
| Collision odds | ~50% only after ~2.7 × 10¹⁸ UUIDs |
| Randomness source | crypto.getRandomValues(), not Math.random() |
| Other versions | v1 time-based, v5 name-based (SHA-1), v7 time-ordered |
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