UUID Generator (v4)

Generate RFC-4122 compliant UUID v4 identifiers in bulk. Cryptographically secure via Web Crypto API.

What is a UUID?

A Universally Unique Identifier (UUID) is a 128-bit value used to uniquely identify resources across systems without coordination. UUIDs are defined by RFC 4122.

UUID Versions

  • v1 — Time + MAC address based
  • v4 — Random (most common, used here)
  • v5 — Namespace + SHA-1 hash
  • v7 — Time-ordered random (newer)

The probability of a v4 UUID collision is astronomically low — you'd need to generate billions per second for decades.

FAQ

Are these UUIDs cryptographically secure?
Yes — generated via crypto.randomUUID() which uses the browser CSPRNG.
When should I use UUIDs vs auto-increment IDs?
UUIDs when records are created on multiple servers (avoids collisions). Auto-increment for single-DB systems where readability matters.