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UUID generator

UUIDs from your browser's cryptographic random numbers. v7 starts with the creation time, so values sort in the order they were made.

How to use

  1. Choose the version and how many.
  2. Change case or hyphens and the list regenerates.
  3. Copy them.

Questions

v4 or v7?

v4 has 122 random bits. v7 puts a 48-bit millisecond timestamp first and fills the rest randomly, so values sort by creation time; that often suits database keys.

Can two collide?

For v4, the chance is negligible even after billions of values.

Does v7 reveal the time?

Yes, the creation time can be read from it. Use v4 where that should stay hidden.

Which standard?

Version and variant bits follow RFC 9562.

Are they stored?

No. They are generated in your browser only.

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