Free UUID Generator
This UUID generator creates random version 4 unique IDs, for database keys, test fixtures, file names and API work, one at a time or in bulk up to 500. Values use cryptographic randomness with correct version and variant bits. Nothing is uploaded.
How it works
Sixteen random bytes come from crypto.getRandomValues; bits are then fixed per RFC 9562, version nibble 4 and variant bits 10, and rendered as the familiar 8-4-4-4-12 hex pattern, e.g. 123e4567-e89b-42d3-a456-556642440000.
Example
| Request | Output shape |
|---|---|
| 1 UUID | xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx |
Frequently asked questions
What is a UUID?
A 128-bit Universally Unique Identifier: 32 hex digits in five groups, used for keys and IDs that must never collide.
What does version 4 mean?
Version 4 UUIDs are randomly generated with fixed version and variant bits. Collisions are vanishingly unlikely.
How many UUIDs can I generate at once?
Between 1 and 500 per batch, as newline-separated text ready for code, CSVs or SQL.
Are these cryptographically random?
Yes. Values come from the browser's cryptographic generator with correct v4 bits set.
Is anything uploaded?
No. Generation happens locally in your browser.
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