UUID generator
Generate random version 4 UUIDs. Choose how many you need and how they are formatted. They are produced by your browser's cryptographic random number generator and never sent anywhere.
1–100
Common questions
What is a version 4 UUID?
A 128-bit identifier with 122 of those bits taken at random; the other six mark the version and variant. Version 4 is the random one, as opposed to versions built from a timestamp or a MAC address.
Can two of these ever collide?
In practice, no. There are 2^122 possible values, so you would need to generate about a billion a second for 85 years to reach a one-in-a-billion chance of a single repeat.
Are these generated on a server?
No. They come from your browser's cryptographic random number generator, the same source used for encryption keys, and are never transmitted. That is also why the box is empty until the page finishes loading.
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