What is a UUID: Definition, Format and Uses
Learn what a UUID is, its 128-bit format, what it is used for and how to generate them for free and securely.
A UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify items in computer systems. Its collision probability is so low that it is safe to generate without central coordination.
1 What it is and its format
A UUID is a string of 32 hexadecimal digits grouped into 5 blocks (8-4-4-4-12), for example 550e8400-e29b-41d4-a716-446655440000.
2 Version 4
Version 4 is generated with cryptographically secure random numbers, making it ideal for most modern applications.
3 What it is used for
Identifying records in databases, API keys, file attachments, sessions and any element that needs a unique identifier.
4 Generate UUIDs
The UUID generator lets you create from 1 to 100 UUID v4 at once and copy them all with a click.
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UUID Generator
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