Online UUID Generator • { Version 4 } •

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit identifier that is globally unique across time and space. Our free online UUID generator creates Version 4 UUIDs, which are randomly generated and have extremely low collision probability.

When to Use UUIDs

UUIDs are essential in many applications:

• Database primary keys when you need uniqueness across systems
• Distributed systems where centralized ID generation isn't feasible
• Session identifiers in web applications
• Tracking entities across different services
• Generating random tokens for security purposes

About Version 4 UUIDs

Version 4 UUIDs are generated using random or pseudo-random numbers. They follow the format:xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxxWhere 'x' is any hexadecimal digit and 'y' is one of 8, 9, A, or B.

UUID Generator Features

Our random UUID generator tool provides:

• RFC 4122 compliant Version 4 UUIDs
• Bulk generation of up to 1000 UUIDs at once
• CSV and TXT download options for generated UUIDs
• One-click copying to clipboard
• 100% free with no registration required

Frequently Asked Questions

How unique are Version 4 UUIDs?

The probability of generating a duplicate UUID v4 is astronomically low. With 122 random bits, there are 5.3×10^36 possible UUIDs. Even generating 1 billion UUIDs per second, the probability of a collision would be extremely small.

Are UUIDs cryptographically secure?

Version 4 UUIDs generated with proper random number generators provide a good level of unpredictability. Our tool uses cryptographically secure random number generation.

Can I use UUIDs in URLs?

Yes, UUIDs are commonly used in URLs as they're URL-safe and don't require encoding. They're particularly useful for REST APIs and resources that need globally unique identifiers.