🆔 UUID/GUID Generator

📚 User Guide

What is UUID?

UUID (Universally Unique Identifier), also known as GUID (Globally Unique Identifier), is a 128-bit identifier used to uniquely identify information in distributed systems.

UUID Format

Standard UUID consists of 32 hexadecimal digits, divided into 5 groups by hyphens:

xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx

• Total length: 36 characters (including 4 hyphens)
• Without hyphens: 32 hexadecimal characters
• Digit 4 indicates UUID version 4 (random)

UUID Features

• Global uniqueness: extremely low collision probability
• No central authority required
• Can be generated independently in distributed systems
• Not dependent on creation time

Use Cases

• Database primary keys
• Unique identifiers in distributed systems
• File names or file IDs
• Session identifiers
• Transaction IDs or order numbers
• API request tracing IDs

UUID vs Auto-increment ID

UUID Advantages:

• Easy to generate in distributed environments
• Does not expose data scale
• No conflicts when merging data

UUID Disadvantages:

• Takes more space (16 bytes)
• Not ideal for database indexing
• Difficult to memorize
• Randomness may affect database performance

Generate UUID in Programming Languages

• JavaScript: crypto.randomUUID()
• Python: import uuid; uuid.uuid4()
• Java: UUID.randomUUID()
• PHP: uniqid() or use ramsey/uuid package
• C#: Guid.NewGuid()