UUID Generator
Generate cryptographically random version 4 UUIDs for use in your code or data.
How It Works
- 1Set how many UUIDs you need.
- 2Click Generate.
- 3Copy or download the list.
Features
- Uses the Web Crypto API for randomness
- Generate up to 100 at once
- Optional uppercase output
Privacy
All processing happens instantly in your browser. Nothing you enter is ever sent anywhere.
About UUID Generator
A UUID (Universally Unique Identifier) is a 128-bit value, usually written as 32 hexadecimal digits split into five groups, like 550e8400-e29b-41d4-a716-446655440000. Version 4, the type this tool generates, fills all of those bits with random data except for a handful of fixed bits that mark it as version 4 — that randomness, rather than any reference to time or hardware, is what gives each UUID its uniqueness.
UUIDs are used anywhere a unique identifier is needed without coordinating with a central authority to hand them out — primary keys in a database, correlation IDs for tracing requests through a system, or unique filenames — precisely because two systems generating UUIDs independently, with no communication between them, will not produce the same value.
This tool generates UUIDs using the Web Crypto API's cryptographically secure random number generator rather than Math.random(), which matters because a weak random source can make generated values more predictable and, in unusual cases, more prone to collisions. With 122 random bits in a v4 UUID, the chance of ever generating a duplicate in practice is negligible even at very large scale.