Free Online UUID Generator

Generate UUID v1, v4, or v7 universally unique identifiers individually or in bulk - Fast, secure, and free

Select UUID Version

Random UUID using cryptographically secure random numbers

Single UUID

Bulk UUID Generator

About UUID Versions

UUID v1

Generated using timestamp and MAC address. Provides uniqueness across machines but may expose hardware information.

UUID v4

Generated using random numbers. Most commonly used. Provides no ordering but excellent randomness and privacy.

UUID v7

Time-ordered using Unix timestamp. Best for database primary keys as it provides natural ordering and indexing benefits.

What is a UUID and Why Use a UUID Generator?

A UUID (Universally Unique Identifier) is a 128-bit number used to uniquely identify information in computer systems. Also known as a GUID (Globally Unique Identifier), UUIDs are designed to be unique across both space and time without requiring a central registration authority. Our free online UUID generator tool helps developers, database administrators, and software engineers create these unique identifiers instantly.

UUIDs are essential for distributed systems, microservices architectures, database primary keys, session identifiers, and any scenario where you need guaranteed unique identifiers without coordination between different systems.

UUID Version Comparison: v1 vs v4 vs v7

UUID v1 - Time-Based UUID Generator

UUID version 1 generates identifiers based on the current timestamp and the MAC address of the computer generating it. This ensures uniqueness across different machines and time. However, because it includes the MAC address, it may expose hardware information, which can be a privacy concern. Use UUID v1 when you need time-based sorting and can accept the potential privacy implications.

UUID v4 - Random UUID Generator

UUID version 4 is the most commonly used UUID type. It generates completely random identifiers using cryptographically secure random number generators. UUID v4 offers excellent privacy and randomness but provides no ordering or time-based information. This makes it ideal for session tokens, API keys, and scenarios where you want maximum randomness and privacy. The probability of collision is astronomically low (1 in 2^122).

UUID v7 - Time-Ordered UUID Generator (Recommended for Databases)

UUID version 7 is the newest standard, designed specifically for modern database systems. It combines Unix timestamp with random data, providing both uniqueness and natural time-based ordering. This makes UUID v7 perfect for database primary keys, as it improves index performance and reduces database fragmentation compared to random UUIDs. If you're building new applications with PostgreSQL, MySQL, MongoDB, or any modern database, UUID v7 is the recommended choice.

Common Use Cases for UUID Generation

  • Database Primary Keys: Use UUID v7 for optimal database performance and natural ordering
  • API Request IDs: Track requests across distributed systems with unique identifiers
  • Session Tokens: Generate secure, unpredictable session identifiers with UUID v4
  • File Names: Create unique file names to prevent conflicts in storage systems
  • Message Queue IDs: Identify messages in distributed queue systems like RabbitMQ or Kafka
  • Microservices: Correlate transactions across multiple services in microservices architectures
  • Testing: Generate bulk test data with unique identifiers for QA and development
  • IoT Devices: Assign unique identifiers to Internet of Things devices

Features of Our Free UUID Generator Tool

  • Multiple UUID Versions: Support for UUID v1, v4, and v7 generation
  • Bulk Generation: Generate up to 100,000 UUIDs at once for large-scale projects
  • Instant Copy: One-click copy to clipboard functionality for quick usage
  • Download Option: Export generated UUIDs as text files for offline use
  • No Registration: Free to use without creating an account or signing up
  • Privacy-Focused: All generation happens in your browser - no data sent to servers
  • Mobile-Friendly: Responsive design works on desktop, tablet, and mobile devices
  • Dark Mode: Eye-friendly dark theme for comfortable use in any lighting

How to Use This UUID Generator

  1. Select your desired UUID version (v1, v4, or v7) based on your use case
  2. For a single UUID, click "Generate UUID" and copy the result
  3. For bulk generation, enter the quantity (up to 100,000) and click "Generate"
  4. Copy all UUIDs to clipboard or download as a text file
  5. Use the generated UUIDs in your application, database, or testing environment

Frequently Asked Questions About UUIDs

Are UUIDs truly unique?

While not mathematically guaranteed, UUIDs are unique enough for all practical purposes. The probability of generating duplicate UUID v4s is approximately 1 in 2^122, which is astronomically low. You could generate billions of UUIDs per second for centuries without a collision.

Which UUID version should I use?

For modern database applications, use UUID v7 as it provides time-based ordering and better index performance. For maximum privacy and randomness (like session tokens), use UUID v4. Use UUID v1 only if you have specific requirements for time-based ordering and MAC address inclusion.

Is this UUID generator secure?

Yes, our UUID generator uses cryptographically secure random number generation provided by your browser's Web Crypto API. All generation happens locally in your browser, ensuring your UUIDs remain private and secure.

Can I use generated UUIDs in production?

Absolutely! UUIDs generated by this tool are production-ready and comply with RFC 4122 standards. They can be safely used in databases, APIs, distributed systems, and any other production environment.