A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify objects in distributed systems. Version 4 UUIDs are randomly generated, making collision probability negligibly small.

What is the difference between UUID and GUID?

GUID (Globally Unique Identifier) is Microsoft's implementation of UUID. They're functionally identical — both are 128-bit identifiers in the same format. 'GUID' is common in .NET/Windows environments; 'UUID' is the universal standard.

How unique is a UUID v4?

UUID v4 is randomly generated from 122 bits of entropy. The probability of generating two identical UUIDs is approximately 1 in 5.3 × 10^36 — for practical purposes, collisions are impossible.

Should I use UUIDs or auto-increment IDs in my database?

UUIDs are better for distributed systems, API-exposed IDs (no sequential enumeration risk), and multi-source data merging. Auto-increment IDs are more compact and perform better for internal, single-database applications.

Are UUID v4s secure as tokens?

UUID v4s are not suitable as security tokens because their format is predictable (known version/variant bits). Use a cryptographically secure random generator (like the Random String Generator) for security tokens.

Text Utilities

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UUID Generator

Generate UUID v4 identifiers. Bulk generate up to 100 UUIDs with copy-all functionality.

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What is UUID Generator?

The UUID Generator creates RFC 4122 compliant Version 4 UUIDs (Universally Unique Identifiers) — 128-bit random identifiers formatted as 8-4-4-4-12 hexadecimal groups (e.g., 550e8400-e29b-41d4-a716-446655440000). Generate single or bulk UUIDs for any development or database need.

UUIDs are the standard for generating unique identifiers in distributed systems, databases, APIs, and modern applications. Unlike auto-increment IDs, UUIDs don't reveal record counts, can be generated client-side, and are safe to use across distributed systems without coordination.

Why Use UUID Generator?

When building applications with distributed databases, multi-tenant systems, or APIs where IDs must be unique without central coordination, UUIDs are the standard solution. This generator creates properly formatted UUIDs instantly without requiring any library or development environment.

Key Features of UUID Generator

✓Generates RFC 4122 Version 4 UUIDs
✓Bulk generation (1 to 1000+ UUIDs at once)
✓Copy single UUID or full list to clipboard
✓Uppercase and lowercase format options
✓Validates existing UUID format

How to Use UUID Generator

1
Set quantity
Enter how many UUIDs you need to generate.
2
Choose format
Select uppercase or lowercase hex format.
3
Generate UUIDs
Click 'Generate UUID' to create your unique identifiers.
4
Copy results
Click 'Copy All' to copy all generated UUIDs to your clipboard.
5
Use in your project
Paste the UUIDs into your database schema, API requests, or development files.