This tool is a free, safe, and efficient online UUID generator. UUID (Universally Unique Identifier) is a software construction standard and part of the Open Software Foundation (OSF) distributed computing environment. It guarantees the global uniqueness of generated IDs without the need for a central control authority.

What is UUID v4?

The most commonly used UUID version is version 4 (UUID v4), which is generated based on random numbers. UUID v4 contains 128 bits (16 bytes) and is typically represented as a 36-character string (32 hexadecimal characters plus 4 hyphens, for example: 123e4567-e89b-12d3-a456-426614174000). Due to its randomness, the collision probability is extremely low and almost negligible.

Main Use Cases

• Database primary key: Used as the primary key for distributed databases (such as MySQL, PostgreSQL, MongoDB), avoiding conflicts with auto-increment IDs during sharding.
• Distributed system tracing: Used as request tracing ID (Trace ID, Request ID) in microservice architectures to link the entire call chain.
• File naming: Used as unique filenames when uploading files, images, or resources to prevent file overwriting.
• Session identifier: Used as a unique identifier for user sessions or temporary tokens.

Tool Features

• Batch generation: Supports generating up to 1000 UUIDs at once, meeting testing or data initialization needs.
• Flexible formatting: Supports one-click conversion to uppercase, hyphen removal (suitable for some databases or API specifications), and adding quotes (convenient for pasting directly into JSON or code).
• Safe and reliable: Prioritizes generation using the browser\'s native crypto.randomUUID() API, ensuring high randomness and security.
• One-click copy and shortcuts: Supports one-click copying of all generated results and Ctrl + Enter shortcut for quick generation.