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UUID Generator

Generate random UUID v4 values locally without sending them anywhere.

Runs locally — input is never uploaded
Ready when you are

WHAT IT DOES

Version 4 UUIDs from your browser's own CSPRNG.

Generate between 1 and 50 random UUID v4 values at once. Randomness comes from crypto.getRandomValues(), the browser's cryptographically secure generator, with the version and variant bits set as RFC 4122 requires. The values are produced on your machine and are known only to you.

Why use it?

Use random UUIDs for fixture IDs, correlation IDs, or records that need independently generated identifiers. Generating an ID does not register it anywhere.

How to use this tool

  1. Set the number of UUIDs and generate them.
  2. Copy the batch to your destination. Each value has the v4 version marker; generating again creates a new batch rather than retrieving the previous one.

Details and limitations

  • Output is lowercase hyphenated 8-4-4-4-12 form, the canonical textual representation.
  • Version bits are set to 4 and the variant bits to RFC 4122, so the results validate against strict parsers.
  • Up to 50 values can be generated in one pass and copied together.
  • No value is ever recorded, so a UUID generated here is not known to any server.

COMMON QUESTIONS

UUID Generator questions

Are these UUIDs safe to use as database keys?
Yes. They are version 4 UUIDs drawn from the browser's cryptographic random source, giving 122 bits of randomness. A collision is not a practical concern.
What is the difference between a UUID and a GUID?
None in practice. GUID is Microsoft's name for the same 128-bit identifier format described by RFC 4122.
Can I use a UUID v4 as a secret or API key?
It is better than a weak token but not ideal. A UUID has a fixed, recognizable structure and 122 bits of entropy. For credentials, prefer the random token generator, which lets you choose the byte length.