UUID Generator
Generate universally unique identifiers (UUID v4) for your projects.
About this tool
The UUID (Universally Unique Identifier) generator is a fundamental tool for developers who need to create unique, non-conflicting identifiers. This tool implements the UUID v4 standard, which generates 128-bit identifiers using random numbers. The probability of collision (generating the same UUID twice) is extremely low, practically negligible for most applications. UUIDs are widely used as primary keys in databases, session identifiers, object tracking, and any scenario where you need a unique identifier that can be generated distributedly without central coordination. The standard format is xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx where x are random hexadecimal digits. The tool processes everything locally in your browser using the native crypto.randomUUID() API, ensuring that identifiers are cryptographically secure and that no information is sent to external servers.
Use cases
- Generate primary keys for distributed databases
- Create unique identifiers for user sessions
- Track objects in distributed systems
- Generate IDs for REST API resources
Frequently asked questions
- What is UUID v4 and how does it differ from other versions?
- UUID v4 is the version that uses random numbers to generate identifiers. Unlike v1 (based on MAC address and timestamp) or v5 (based on hash), v4 doesn't require system information and is simpler to implement.
- Is a generated UUID really unique?
- The probability of collision in UUID v4 is extremely low (1 in 2^122). For most practical applications, it can be considered unique. However, for critical systems with billions of records, consider other methods.
- Can I use UUIDs as primary keys in databases?
- Yes, UUIDs are common as primary keys. However, note that they are longer than auto-incrementing integers, which can affect database performance and storage size.
- Are the generated UUIDs cryptographically secure?
- Yes, this tool uses crypto.randomUUID() from the browser, which generates cryptographically secure UUIDs using a secure random number generator.