Free UUID Generator Online

Need a unique identifier for your app, database or API? Our free UUID generator online creates random version 4 UUIDs in one click — no signup, no install, and nothing leaves your browser.


About the Free UUID Generator

A UUID — a universally unique identifier — is a 128-bit value written as 36 characters in five groups, like 550e8400-e29b-41d4-a716-446655440000. Software uses UUIDs as database keys, session tokens, file names and API ids because two random UUIDs are practically never the same. This free UUID generator online makes version 4 UUIDs, the random kind described in RFC 4122. The third group always starts with 4, and the fourth group starts with 8, 9, a or b, which marks it as a real v4 UUID.

Everything runs in your browser with the built-in crypto random number generator, so the UUIDs are unpredictable and nothing is sent to a server. Generate one UUID for a single record, or generate 10 at once for a batch of test data. Need a compact form without dashes? Tick "Generate without hyphens" to get the 32-character version instead. Copy the whole list in one click and paste it into your code, spreadsheet or database.

How to Use the UUID Generator

  1. Choose how many UUIDs you need — 1, 5 or 10.
  2. Click Generate UUIDs. A fresh random UUID appears instantly.
  3. Click Copy UUIDs to copy the list, or tick "Generate without hyphens" first for the compact 32-character form.

Frequently Asked Questions

What is a UUID?

A UUID is a 128-bit unique identifier, usually written as 36 characters in five groups separated by hyphens. It is used as a database key, a session id, a file name or an API identifier because duplicate UUIDs are almost impossible.

Are the UUIDs really unique?

Version 4 UUIDs use 122 random bits, so the chance of two matching is about 1 in 5.3 thousand billion billion billion billion. For everyday use they are treated as unique.

What does version 4 mean?

Version 4 means the UUID is randomly generated. You can tell by the third group, which always starts with the digit 4, and the fourth group, which starts with 8, 9, a or b.

Can I use these UUIDs in my database?

Yes. Most databases, including MySQL, PostgreSQL, MongoDB and SQLite, accept UUIDs as primary keys or unique ids, and programming languages like JavaScript, Python and Java have built-in UUID support.

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