UUID Generator

Generate v4 UUIDs instantly

About This Tool

Our UUID generator creates RFC 4122 compliant version 4 UUIDs (Universally Unique Identifiers) using cryptographically secure randomization. Generate single or multiple UUIDs instantly for database primary keys, session identifiers, API request tracking, file naming, and distributed system coordination with guaranteed global uniqueness.

What is a UUID?

A UUID (Universally Unique Identifier) is a 128-bit identifier standardized by RFC 4122, displayed as 36 characters in the format 8-4-4-4-12 hexadecimal digits (example: 550e8400-e29b-41d4-a716-446655440000). Version 4 UUIDs are randomly generated using cryptographically secure random number generation, ensuring a collision probability so astronomically low (1 in 2^122) that they can be considered globally unique without central coordination. This makes UUIDs perfect for distributed systems where multiple components need to generate unique identifiers independently without communication or synchronization.

Key Features

  • RFC 4122 Compliance: Generates standard version 4 UUIDs that work across all platforms and programming languages
  • Cryptographic Randomness: Uses crypto.randomUUID() for true random generation, not pseudo-random algorithms
  • Bulk Generation: Create up to 100 UUIDs at once for batch operations or database seeding
  • Individual Copy: Copy any single UUID with dedicated copy buttons for quick access
  • Copy All Function: Copy all generated UUIDs at once, newline-separated for easy pasting into scripts or data files
  • Zero Dependencies: Uses native browser APIs without external libraries for maximum reliability
  • Instant Generation: Generate UUIDs in milliseconds with no server round trips

Common Use Cases

UUIDs solve identification challenges across countless software development and system architecture scenarios.

  • Database Primary Keys: Use UUIDs as primary keys in distributed databases to avoid ID conflicts during replication or merging
  • Session Identifiers: Generate unique session IDs for user authentication and session management in web applications
  • File and Resource Naming: Create guaranteed-unique filenames for uploads, temporary files, or cloud storage objects
  • API Request Tracking: Assign correlation IDs to track requests across microservices and distributed logging systems
  • Message Queue IDs: Identify messages uniquely in systems like RabbitMQ, Kafka, or AWS SQS
  • Entity Identifiers: Generate IDs for entities in object-oriented systems or document databases like MongoDB
  • Distributed Systems: Coordinate between services without requiring centralized ID generation or management

How to Use

Generating UUIDs is quick and straightforward with our simple interface.

  1. Enter the number of UUIDs you need to generate (1-100) in the count field
  2. Click "Generate UUIDs" to create your requested number of unique identifiers
  3. Each UUID appears with its own "Copy" button for individual use
  4. Use "Copy All" to copy all generated UUIDs at once, separated by newlines
  5. Paste the UUIDs into your code, database, configuration file, or wherever needed
  6. Generate additional UUIDs anytime without limits or restrictions

UUID Versions and Formats

While several UUID versions exist (v1 through v5), version 4 is the most commonly used in modern applications. UUID v1 uses timestamp and MAC address, which can expose information about when and where the UUID was generated. UUID v3 and v5 use namespace-based hashing (MD5 and SHA-1 respectively), suitable when you need deterministic UUIDs from the same input. UUID v4, which this tool generates, uses pure randomness making it ideal for most applications where you simply need a unique identifier without exposing any information. The standard format includes hyphens, but some systems may use a continuous 32-character hex string by removing the hyphens.

UUIDs vs Auto-Increment IDs

Traditional auto-increment integers (1, 2, 3...) have limitations in distributed systems - they require central coordination and create merge conflicts when combining data from multiple sources. UUIDs can be generated independently across different systems without collisions, making them perfect for microservices, offline-first applications, and distributed databases. However, UUIDs consume more storage space (128 bits vs 32 or 64 bits) and aren't naturally ordered, which can impact database index performance. Choose UUIDs when distribution and global uniqueness matter more than storage efficiency and sequential ordering.

Technical Implementation

This tool uses the browser's native crypto.randomUUID() method introduced in modern browsers, which generates RFC 4122 version 4 UUIDs using the Web Crypto API's cryptographically strong random number generator. The method automatically formats the UUID with hyphens in the standard 8-4-4-4-12 pattern and sets the appropriate version and variant bits according to the RFC 4122 specification. All generation happens client-side in your browser, ensuring privacy and eliminating network latency. Generated UUIDs are statistically guaranteed to be unique across all systems and time without requiring any central authority or database lookup.