UUID Generator
Generate RFC 4122 version 4 UUIDs locally in your browser.
About UUID v4
UUID v4 values are randomly generated identifiers commonly used for database keys and request ids. Generation happens entirely in your browser.
Learn More About UUID Generation
Complete Guide to UUID Generation: Understanding Unique Identifiers
Explore the world of UUIDs, learn about different versions, understand their applications in modern software development, and discover best practices for implementation.
About this UUID Generator
Generate RFC 4122 compliant UUIDs (Universally Unique Identifiers) instantly. UUIDs are 128-bit identifiers that are guaranteed to be unique across time and space, making them perfect for database primary keys, distributed systems, API identifiers, and any application requiring unique identifiers without central coordination.
Key Features
Generate RFC 4122 version 4 (random) UUIDs
Cryptographically secure random number generation
Generate single or multiple UUIDs at once
Copy UUIDs to clipboard with one click
Standard UUID format (8-4-4-4-12 hexadecimal format)
Guaranteed uniqueness across all generated UUIDs
No registration or coordination required
Works entirely in your browser for privacy
How to Use
Click 'Generate UUID' to create a new random UUID
The UUID will be displayed in standard format (e.g., 550e8400-e29b-41d4-a716-446655440000)
Use the copy button to copy the UUID to your clipboard
Generate multiple UUIDs if you need several unique identifiers
Each generated UUID is guaranteed to be unique
Use the UUIDs directly in your applications, databases, or APIs
Popular Use Cases
Create unique primary keys for database records
Generate unique identifiers for distributed systems
Create unique IDs for API endpoints and resources
Generate unique identifiers for file uploads and storage
Create unique session IDs and transaction identifiers
Generate unique identifiers for microservices and containers
Create unique IDs for user accounts and profiles
Generate unique identifiers for event tracking and analytics
Tips & Best Practices
UUIDs are 128 bits long and represented as 32 hexadecimal digits in 5 groups
Version 4 UUIDs use random numbers, ensuring no collisions
UUIDs are case-insensitive but typically displayed in lowercase
Store UUIDs as strings or binary data depending on your database
Use UUIDs when you need globally unique identifiers without a central authority
Consider using UUIDs for distributed systems where sequential IDs won't work
UUIDs are larger than sequential integers, so consider storage implications
Frequently Asked Questions
What is a UUID?
A UUID (Universally Unique Identifier) is a 128-bit identifier standardized by RFC 4122. Version 4 UUIDs use random numbers, ensuring uniqueness without coordination.
Are UUIDs really unique?
While collisions are theoretically possible, the probability is astronomically low (about 1 in 5.3 × 10^36). For practical purposes, UUIDs can be considered unique.
What's the difference between UUID and GUID?
UUID and GUID (Globally Unique Identifier) are essentially the same thing. GUID is Microsoft's term for UUID, but they follow the same RFC 4122 standard.
Can I use UUIDs as database primary keys?
Yes, UUIDs are commonly used as primary keys, especially in distributed systems. However, they're larger than integers and may impact performance in some databases, so consider your specific use case.