UUID Generator
A UUID (Universally Unique Identifier) is a 128-bit identifier used to uniquely identify resources in distributed systems. UUIDs are essential in software development for database primary keys, API identifiers, session tokens, and message correlation IDs where globally unique values are needed without central coordination.
This tool generates UUIDs in three versions: v1 (timestamp-based, includes creation time), v4 (fully random, the most commonly used), and v7 (Unix timestamp + random, sortable by creation time per RFC 9562). Each version has different trade-offs between uniqueness, privacy, and sortability.
How it works
UUID v4 uses 122 random bits, giving 2^122 (≈5.3 × 10^36) possible values. The probability of a collision after generating 1 billion UUIDs is approximately 2.7 × 10^-20, making duplicates virtually impossible in practice.
Use cases
- Generating unique database primary keys without auto-increment
- Creating correlation IDs for distributed system tracing
- Assigning unique identifiers to API resources and entities
- Testing applications that require UUID inputs