Free Online UUID v4 Generator
Generate random UUID v4 (GUID) identifiers instantly. Choose how many to generate and customize the output format.
How to Use the UUID Generator
1. Choose Your Options
Select the number of UUIDs to generate (1, 5, 10, or 50), pick lowercase or uppercase, and optionally remove the hyphens.
2. Click Generate
Each UUID v4 is generated locally in your browser using a cryptographically secure random source.
3. Copy Your UUIDs
Click the copy icon next to any UUID to copy it individually, or use Copy All to copy the entire list to your clipboard.
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information across computer systems. A UUID v4 is randomly generated, making it ideal for database primary keys, session tokens, request IDs, and any scenario where you need an identifier that is practically guaranteed to be unique.
UUIDs are also called GUIDs (Globally Unique Identifiers), a term popularized by Microsoft. The standard v4 format contains 36 characters, including four hyphens, and uses the hexadecimal digits 0-9 and a-f. Because the number of possible combinations is astronomically large (2122 for version 4), collisions are effectively impossible.