UUID generator · Guide
UUID Generator Online: Random v4 Identifiers
A UUID generator produces universally unique identifiers — 128-bit values that are practically guaranteed not to collide. This guide explains UUID v4 and where these identifiers fit.
What a UUID v4 is
A version 4 UUID is mostly random: 122 random bits formatted as 36 characters with hyphens. The randomness makes collisions astronomically unlikely, so you can generate IDs independently without coordination.
This generator uses the browser cryptographic random source, so the values are suitable as unpredictable identifiers, and it runs locally.
Where UUIDs help
They are ideal as primary keys, request IDs, and identifiers for test fixtures and mock records — anywhere you need uniqueness without a central counter.
Frequently asked questions
Can two generated UUIDs ever collide?
In theory yes, but the probability is so small it is treated as zero in practice. You can generate v4 UUIDs independently and rely on them being unique.
Ready to try it?
Open the free browser-based UUID generator and apply what you just read — no sign-up, runs locally.
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