finetoolbox

GUID Generator

Generate random GUIDs (UUID v4) instantly in your browser. One click to copy, optional auto copy. Nothing is sent to a server.

What is a GUID?

A GUID (Globally Unique Identifier), also called a UUID (Universally Unique Identifier), is a 128-bit value used to identify records, objects or messages without a central authority handing out numbers. It is written as 32 hexadecimal digits in five groups, for example 3f2b8c1e-9d4a-4c6b-8e2f-1a7d5b0c9e34.

What is a version 4 UUID?

This tool generates version 4 UUIDs as defined in RFC 9562. Apart from six fixed bits that mark the version (the 4 at the start of the third group) and the variant (8, 9, a or b at the start of the fourth group), all 122 remaining bits are random. The chance of two v4 UUIDs colliding is so small that it can be ignored in practice.

Is it safe to use these GUIDs?

Yes. GUIDs are generated locally in your browser with the Web Crypto API (crypto.randomUUID()), a cryptographically secure random number generator. Nothing is sent to or stored on a server.

How does auto copy work?

Turn on Auto copy and every new GUID is copied to your clipboard as soon as it is generated, so you can paste it straight away. The setting is remembered in your browser.

GUID vs UUID: is there a difference?

No practical difference. “GUID” is the name commonly used in the Microsoft ecosystem (.NET, SQL Server, Windows), while “UUID” is the name used in the RFC and most other platforms. Both refer to the same 128-bit format.