A Universally Unique Identifier (UUID) is a 128-bit number used to identify information in computer systems.
Why Not Just Use Auto-Incrementing IDs?
In a single database, auto-incrementing IDs (1, 2, 3...) work fine. But in distributed systems with multiple databases, guaranteeing uniqueness without a central authority requires UUIDs.
UUID Versions
- •v1: Based on MAC address and date-time.
- •v4: Completely random. This is the most common version used today, relying on cryptographic randomness to avoid collisions.
Need to generate some keys for testing? Use our instant, client-side UUID Generator to create up to 100 valid v4 UUIDs at a time.