UUID v4 Generator
Generate random version 4 UUIDs with your browser's cryptographic random source. Create up to 50 identifiers and copy them in the format your application expects.
About UUID version 4
A UUID is a 128-bit identifier designed to be unique without coordinating with a central database. Version 4 UUIDs are generated from random data, making them useful for database keys, request identifiers, test fixtures, filenames, and distributed systems.
This tool uses the browser's cryptographic random-number generator, then sets the UUID version and variant bits required by the current UUID specification. Generation happens locally, so the UUIDs are not submitted to MiniUtil.
Output format
A standard UUID contains 32 hexadecimal characters in five hyphen-separated groups:
xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
The 4 identifies version 4. The first hexadecimal character in the fourth group encodes the UUID variant. Uppercase, braces, and omitted hyphens are presentation choices; they do not change the underlying 128-bit value.
How to use it
- Choose how many UUIDs you need.
- Select optional uppercase, braces, or compact formatting.
- Generate the identifiers.
- Copy one UUID or the full list.
Practical guidance
- Version 4 is a strong general-purpose choice when identifiers do not need to be sortable.
- Keep a database uniqueness constraint for application-level protection.
- UUIDs are identifiers, not secrets. Do not use them as passwords, session tokens, or authorization checks.
- If you need Microsoft-style defaults, use the GUID Generator for .NET and Windows.
The tool works in modern browsers that provide the Web Crypto API.