Free Online UUID Generator & Analyzer

Generate cryptographically secure Universally Unique Identifiers (UUIDs) and GUIDs for development, databases, and distributed systems. Support for all UUID versions with detailed analysis.

v4: Random (most common), v1: Time-based with MAC address, v3/v5: MD5 hash of namespace and name/SHA-1 hash of namespace and name, v6/v7: Time-ordered (modern)/Unix epoch timestamps
Generate 1-100 UUIDs at once
ULID Generator

About UUID Generator

The UUID Generator is a powerful tool for creating Universally Unique Identifiers (UUIDs), also known as Globally Unique Identifiers (GUIDs). UUIDs are 128-bit identifiers that are designed to be unique across space and time, making them ideal for distributed systems, databases, and applications that require unique identification without central coordination.

This tool supports all major UUID versions: UUID v1 generates time-based identifiers with MAC address information, UUID v3 creates deterministic UUIDs using MD5 hashing of a namespace and name, UUID v4 produces truly random identifiers, UUID v5 uses SHA-1 hashing for better security, UUID v6 provides time-ordered identifiers with improved performance, UUID v7 uses Unix epoch timestamps for modern applications, and UUID v8 allows for custom implementations.

Common use cases include database primary keys, session identifiers, transaction IDs, API request tracking, distributed system coordination, file system identifiers, and unique resource locators. The tool provides detailed information about each generated UUID, including version, variant, timestamp (where applicable), node information, and various format representations (hex, bytes, integer, URN).

For more information about UUID specifications and best practices, visit the RFC 4122 specification, UUID v6/v7/v8 draft, and Wikipedia UUID article.

Technical Information

UUID Structure & Format

A UUID is a 128-bit identifier typically represented as 32 hexadecimal digits, displayed in five groups separated by hyphens, following the pattern 8-4-4-4-12. The structure includes version and variant bits that determine the UUID type and ensure uniqueness across different implementations.

Security & Reliability

Our UUID generator uses cryptographically secure random number generation for v4 UUIDs and follows RFC 4122 specifications for all versions. Generated UUIDs are suitable for high-security applications including financial systems, healthcare databases, and enterprise software.

Collision Resistance

The probability of generating duplicate UUIDs is astronomically low. Even generating 1 billion UUIDs per second for 100 years would result in only a 50% chance of a single collision, making UUIDs effectively unique for practical purposes.

Standards Compliance

All generated UUIDs comply with RFC 4122 specifications, ensuring compatibility with standard libraries and tools across different programming languages and platforms.

Applications & Use Cases

Database Design

Use UUIDs as primary keys in distributed databases, avoiding conflicts when merging data from multiple sources or implementing sharding strategies.

API Development

Generate unique request IDs, session tokens, and resource identifiers for REST APIs and microservices architectures.

Distributed Systems

Create unique identifiers across multiple nodes, services, and data centers without requiring centralized coordination.

File Systems

Generate unique file identifiers, volume IDs, and storage system references for modern file systems and cloud storage.

Session Management

Create secure session identifiers, authentication tokens, and user session tracking across web applications.

Transaction Tracking

Generate unique transaction IDs for financial systems, e-commerce platforms, and payment processing.

Frequently Asked Questions

UUID (Universally Unique Identifier) and GUID (Globally Unique Identifier) are essentially the same thing. GUID is Microsoft's implementation of the UUID standard. Both follow RFC 4122 specifications and can be used interchangeably in most applications.

Use UUID v4 for most applications requiring random uniqueness. Use v1 for time-ordered data, v3/v5 for deterministic generation based on namespaces, and v6/v7 for modern applications requiring better database performance.

While not mathematically guaranteed to be unique, UUIDs are practically unique. The probability of collision is so low that it's negligible for real-world applications. Even generating billions of UUIDs would have an extremely low chance of duplicates.

Yes, UUIDs are excellent for primary keys, especially in distributed systems. However, consider using v6 or v7 UUIDs for better database performance, as they are time-ordered and reduce index fragmentation.

UUID v4 generated with cryptographically secure random number generation is suitable for high-security applications. The randomness makes them unpredictable and secure for use in authentication tokens, session IDs, and other security-sensitive contexts.