UUID Generator

Generate cryptographically secure UUID v4 (random) identifiers for unique identification across systems.

UUID Generator

Generate cryptographically secure UUID v4 identifiers.

Generated UUID

About UUIDs

Universally Unique Identifiers (UUIDs) are 128-bit values guaranteed to be unique across time and space. This generates UUID v4 (random) identifiers.

Common uses:

Database primary keys
API request tracking IDs
Session identifiers
File and resource naming
Distributed system coordination

What are UUIDs?

Universally Unique Identifiers (UUIDs) are 128-bit values designed to be unique across time and space without requiring a central coordinating authority.

UUID v4 Structure

xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

Length: 36 characters (32 hex + 4 hyphens)

Format: 8-4-4-4-12 hexadecimal digits

Version: 4 (random/pseudo-random)

Uniqueness: 2^122 possible values

Common Use Cases

Database Design

Create users table with distributed-safe UUIDs

API Development

File Management

Microservices

Correlation IDs: Track requests across services

Event IDs: Unique event identification

Resource IDs: Distributed resource identification

Advantages Over Sequential IDs

aspect	uuid	sequential id
Uniqueness	Globally unique	Database unique only
Predictability	Unpredictable	Easily guessable
Distribution	Works offline	Requires coordination
Security	No information leakage	Reveals count/timing
Merging	No conflicts	Requires ID remapping

Best Practices

Use for distributed systems

Store as UUID type in databases (not string)

Use for public APIs to prevent enumeration

Generate on client-side when possible

Consider performance impact in high-frequency scenarios

Not suitable for sorting by creation time