Choose how many UUIDs you need and generate them below. Everything runs in your browser using a cryptographically secure random source — nothing is sent to our server.
Generated locally in your browser — nothing is sent to our server.
Computed entirely in your browser — nothing you enter here is sent to our server.
Generating…
Validate a UUID
Structural check only (RFC 4122 shape/version/variant) — there is no registry of "real" UUIDs to check against.
About UUIDs
A UUID (Universally Unique Identifier) is a 128-bit value formatted as 32 hexadecimal characters in 5 groups (e.g. f47ac10b-58cc-4372-a567-0e02b2c3d479). This tool generates version 4 UUIDs — the random variant defined in RFC 4122 — using your browser’s crypto.randomUUID() where available (with a manual, equally random fallback on older browsers), so the chance of any two generated UUIDs ever colliding is astronomically small. Commonly used as database primary keys, request IDs, or any identifier that needs to be unique without central coordination.
FAQ
Is my data uploaded anywhere?
Nothing you’d need to upload — this tool takes no input beyond how many UUIDs to generate, and the UUIDs themselves are generated entirely in your browser.
Can two UUIDs generated by this tool ever collide?
In theory yes, in practice no — with 122 random bits, you’d need to generate roughly a billion UUIDs per second for about 85 years before a 50% chance of any collision.
What’s the difference between UUID versions?
Different UUID versions derive their bits differently (e.g. version 1 from timestamp + hardware address, version 5 from a hash of a namespace + name). Version 4 — purely random — is the most common choice today since it needs no external coordination and reveals nothing about when or where it was generated.