Generate UUIDs
Create version 4 UUIDs using your browser's own crypto library.
What to know
UUIDs are produced by crypto.randomUUID(), the browser's own implementation, which draws on the operating system's cryptographic random source. These are version 4 — 122 random bits.
Collisions are not a practical concern: you would need to generate around a billion UUIDs per second for roughly 85 years to reach a 50% chance of a single duplicate.
Questions
Is anything uploaded to a server?
No. Every tool on this site runs inside your browser using standard web APIs. There is no upload, no account, no logging and no server holding your data afterwards. You can confirm it by opening your browser's developer tools and watching the network tab stay empty while you work.