UUID Generator
Generate one or many random version 4 UUIDs instantly using your browser's built-in secure random number generator — nothing is sent to a server.
Options
Generated UUIDs
How to generate UUIDs
- Set how many UUIDs you need and pick any formatting options (uppercase, no hyphens, braces).
- Click Generate to create them instantly using your browser's secure random number generator.
- Copy them all at once, or download the full list as a text file.
What is a UUID, and how random is it?
A UUID (universally unique identifier) is a 128-bit value typically written as 32 hex digits split into five groups, like 3fa85f64-5717-4562-b3fc-2c963f66afa6. This tool generates version 4 UUIDs, meaning almost all of those bits come from a cryptographically secure random number generator rather than being derived from a timestamp or hardware address. The chance of two version 4 UUIDs ever colliding is astronomically small — you'd need to generate roughly a billion IDs per second for about 85 years before a 50% chance of a single collision.
Common uses for UUIDs
| Use case | Why a UUID fits |
|---|---|
| Database primary keys | Unique across tables and systems without a central counter |
| Distributed systems | Multiple servers can generate IDs independently with no coordination |
| Session or request IDs | Safe to expose publicly without revealing sequence or volume |
| File or object naming | Avoids naming collisions when files are created by many sources |
FAQ
Is this UUID generator free and private?+
Yes. Every UUID is generated locally using the Web Crypto API built into your browser — nothing is transmitted anywhere.
Are these UUIDs guaranteed to be unique?+
Not mathematically guaranteed, but the probability of a collision is so small in practice that version 4 UUIDs are treated as unique for virtually all real-world purposes.
What UUID version does this generate?+
Version 4 — the random-based variant defined in RFC 4122, and the most commonly used version for general-purpose unique identifiers.
Tools for Developers
How This Generator Works
Each UUID is generated locally using the Web Crypto API built into your browser, following the RFC 4122 version 4 format — nothing is transmitted to a server or stored anywhere.
Last updated: August 28, 2026.
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