UUID Generator
Generate one or a hundred random UUIDs at once. Also produces short, URL-friendly ids when a 36-character UUID is more than you need.
UUID v4 uses 122 random bits, so the chance of a collision is negligible even across billions of ids. Values come from your browser cryptographic random source and are never sent anywhere.
Frequently Asked Questions
What is a UUID v4?
A 128-bit identifier where 122 bits are random. The version and variant bits are fixed, which is why every v4 UUID has a 4 at the start of the third group.
Can two UUIDs collide?
In theory yes, in practice no. You would need to generate about 2.7 quintillion UUIDs before the chance of a single collision reaches even one in a billion.
When should I use a short ID instead?
When the id appears in a URL that people see or type. A 21-character short id has roughly the same collision resistance as a UUID but is far more compact — useful for share links and public-facing routes.
Are these UUIDs generated on your server?
No. They are produced in your browser by crypto.randomUUID, so no request is made and nobody else ever sees the values.