What is UUID Generator?

When you need unique IDs for databases or want to create identifiers that won't collide in distributed systems—this tool can help. UUID (Universally Unique Identifier) generates 128-bit long unique identifiers with an extremely low probability of collision anywhere in the world.

• Supports Version 1 (timestamp-based) and Version 4 (random)
• Customizable hyphen presence and uppercase/lowercase
• Can generate up to 100 UUIDs at once

Useful for database primary keys, session management, transaction identification, file name uniqueness, and many other scenarios.

How to Use

Select the UUID version, configure hyphen and uppercase options, then click the "Generate UUID" button. Generated UUIDs will appear in the result area.

You can specify the quantity to create multiple UUIDs at once (1-100).

Generation Examples

Version 4 with hyphens in lowercase:

f47ac10b-58cc-4372-a567-0e02b2c3d479

Version 1 without hyphens in uppercase:

5A99E9E01C8A11E8AEFF362B9E155667

UUID Versions

Version 1 - Timestamp-Based

Generated by combining timestamp information at generation time with a node ID (typically MAC address).

Features

• Can be sorted chronologically
• Efficient for database indexing
• Generation time can be identified later

Considerations

• Contains MAC address, so caution needed in privacy-sensitive cases
• Depends on clock accuracy

Version 4 - Random Generation

Generated from completely random values. The most commonly used UUID version.

Features

• No information leaks from generation patterns
• Suitable for privacy-focused applications
• Extremely low collision probability even with parallel generation in distributed systems

Considerations

• Randomness may reduce database index efficiency
• Cannot be sorted by generation order

Benefits of UUID

Extremely Low Collision Probability

With properly implemented UUID generation, collision probability is negligible (approximately 10^-37).

Ideal for Distributed Systems

Multiple systems can generate independently without central coordination, making them suitable for distributed environments.

Standardized

Standardized by ISO/IEC 9834-8:2005 and RFC 4122, supported by virtually all programming languages.

Important Notes

• UUIDs are 32 characters plus hyphens in length, which may not be suitable when short identifiers are needed
• Version 4 is randomly generated, so consecutive generations won't produce adjacent values
• For critical security uses like encryption keys, consider using dedicated cryptographic random number generators