Generators
UUID Generator
Generate RFC 4122 v4 UUIDs — one at a time, or up to 1,000 in bulk. Uses the Web Crypto API, entirely in your browser.
UUID v4
—
Bulk generate
Max 1,000
Results
UUID structure
A UUID is written as 32 hexadecimal digits grouped as8-4-4-4-12 (e.g. xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx). The version (here, always 4) is encoded in the first digit of the third group, and the variant is encoded in the first digit of the fourth group.
Common use cases
- Primary keys for database rows, generated client-side or server-side
- Idempotency keys for API requests
- Correlation/trace IDs for distributed logging
- Unique filenames or object storage keys
Frequently asked questions
- What is a UUID?
- A Universally Unique Identifier (UUID) is a 128-bit value, typically written as 32 hex digits in the form 8-4-4-4-12, designed so that generating one independently anywhere is astronomically unlikely to collide with another.
- What's special about version 4?
- Version 4 UUIDs are generated from random (or pseudo-random) bits rather than from a timestamp or hardware address, per RFC 4122. This tool uses the Web Crypto API's crypto.randomUUID(), which is cryptographically secure.
- Are these UUIDs generated on a server?
- No — every UUID here is generated locally in your browser using crypto.randomUUID(). Nothing is transmitted or logged.
- Can I generate more than one at a time?
- Yes — use the bulk generator below to create up to 1,000 UUIDs at once, one per line.