UUID Generator

Generate one or hundreds of UUIDs (also called GUIDs) with a click.

Free · Runs in your browser · Your text is never uploaded

A unique identifier code made of random characters

UUID versions

A UUID (universally unique identifier) is a 128-bit value written as 32 hex digits in the pattern xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx. Because the space is so large, two randomly generated UUIDs will not realistically collide.

  • Version 4 is almost entirely random and is the most common choice.
  • Version 7 starts with a millisecond timestamp followed by random bits, so values sort by creation time. That makes them friendlier to database indexes than v4.

Values are created with your browser’s cryptographically secure random number generator. “GUID” is Microsoft’s name for the same thing, often written in uppercase.

Popular uuid generator presets

Frequently asked questions

Are UUIDs really unique?

Not guaranteed, but a random v4 collision is so improbable that it is treated as impossible in practice.

What is the difference between a UUID and a GUID?

They are the same format. GUID is the term used in Microsoft environments.

Should I use v4 or v7 as a database key?

v7 is usually better for large tables since new rows land near each other in the index, while v4 spreads inserts randomly.

Are these generated securely?

Yes. They use crypto.getRandomValues in your browser, not Math.random.

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