UUID Generator

UUID/GUID Generator

Generate universally unique identifiers (UUIDs) in multiple versions and formats for your applications.

Generator Options
Generated UUIDs
UUID v4
Random

Random UUID (most common)

Best for:

General purpose unique identifiers

UUID Versions

UUID v1 (Timestamp)

Based on timestamp and MAC address. Provides time ordering but may reveal information about the generator.

UUID v4 (Random)

Randomly generated. Most commonly used version. Provides good uniqueness with no information leakage.

Nil UUID

Special UUID with all bits set to zero. Used to represent null or empty UUID values.

Common Use Cases

Database Primary Keys

Unique identifiers for database records across distributed systems.

API Request IDs

Track and correlate API requests and responses for debugging.

File Names

Generate unique file names to prevent conflicts in storage systems.

Session IDs

Create secure, unpredictable session identifiers for web applications.

UUID Format & Structure

UUIDs are 128-bit identifiers typically represented as 32 hexadecimal digits in the format:

xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx
  • M indicates the UUID version (1, 4, etc.)
  • N indicates the UUID variant (usually 8, 9, A, or B)
  • Total length: 36 characters including dashes, 32 without dashes
  • Probability of collision: Virtually zero for practical purposes

UUIDs are standardized by RFC 4122 and are widely supported across programming languages and databases.