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UUID / ULID Generator
Generate v4 UUIDs or ULIDs in bulk, one click to copy. Uses your browser's cryptographically secure random number generator.
🔒 Runs entirely in your browser — no data is ever sent anywhereResults (one per line)
Frequently asked questions
What's the difference between a UUID and a ULID?
A v4 UUID is 128 bits of random data with no inherent ordering. A ULID encodes a timestamp in its first 48 bits, so ULIDs generated later always sort after earlier ones — useful for database primary keys where you want both uniqueness and chronological order.
Are the generated UUIDs cryptographically random?
Yes — this tool uses the browser's crypto.getRandomValues() API, a cryptographically secure random number generator, not Math.random().
Can two generated UUIDs ever collide?
Technically possible but astronomically unlikely: a v4 UUID has 122 random bits, so you'd need to generate roughly a trillion per second for a billion years before a 50% chance of one collision.